ADR-0024 Phase D (full): schema-aware value typing

Schema-aware typed value slots — the central design claim of
ADR-0024 §Phase D. Insert / update / delete value slots now
dispatch on the user-facing column type at parse time, rejecting
mis-shaped input with localised wording instead of waiting for
the bind-time error.

What changed:

**SchemaCache extension** (`src/completion.rs`):
- New `TableColumn { name, user_type }` for per-table column
  metadata.
- `SchemaCache.table_columns: HashMap<String, Vec<TableColumn>>`.
- `SchemaCache::columns_for_table(name)` — case-insensitive
  lookup, mirrors the walker's case-insensitive entry-word
  resolution.

**WalkContext schema plumbing** (`src/dsl/walker/context.rs`):
- `WalkContext<'a>` gains a lifetime and a `schema: Option<&'a
  SchemaCache>`. `WalkContext::new()` keeps the schemaless
  default; `with_schema(s)` is the new schema-aware constructor.

**Parser entry point** (`src/dsl/parser.rs`):
- `parse_command_with_schema(input, schema)` is the new public
  schema-aware variant. `parse_command(input)` becomes a thin
  wrapper that delegates with `None` for back-compat.
- Internal `try_walker_route` accepts an `Option<&SchemaCache>`
  and threads it into the WalkContext.

**Node::Ident writes_table/writes_column** (`src/dsl/grammar/mod.rs`):
- Two new fields on `Node::Ident`. When `writes_table: true` and
  `source: Tables`, the walker writes the matched ident's name
  into `current_table` and resolves `current_table_columns`
  against the schema cache. When `writes_column: true` and
  `source: Columns`, the walker writes the resolved
  `TableColumn` into `current_column`.

**Walker driver DynamicSubgrammar dispatch** (`src/dsl/walker/driver.rs`):
- The `Node::DynamicSubgrammar(factory)` branch now resolves the
  factory at walk time and `Box::leak`s the result so its inner
  static-slice fields (Choice/Seq) have the lifetime the walker
  expects (per ADR-0024 §sub-grammars). The leak is bounded by
  command-shape complexity per walk; per-walk arena is a future
  optimisation.
- `walk_ident` extends to perform the schema writes when the
  flags are set.

**Typed value slot factories + dynamic sub-grammars** (`src/dsl/grammar/shared.rs`):
- `int_slot` / `real_slot` / `decimal_slot` / `bool_slot` /
  `text_slot` / `date_slot` / `datetime_slot` / `blob_slot` —
  one per `Type`. Each accepts the appropriate literal kind plus
  `null`; integer-only validator rejects `3.14` at int columns;
  decimal validator pins numeric shape.
- `slot_for_type(ty) -> Node` is the dispatcher.
- `current_column_value(ctx) -> Node` is the dynamic sub-grammar
  for `set col = …` and `where col = …` values; reads
  `current_column` and dispatches via `slot_for_type`.
- `column_value_list(ctx) -> Node` is the dynamic sub-grammar
  for `insert into T values (…)`; reads `current_table_columns`
  and unfolds a Seq of typed slots separated by commas.
- Both fall back to the schemaless `VALUE_LITERAL` choice when
  the context lacks the schema-resolved entries — keeps
  schemaless `parse_command` callers (tests, replay path)
  working.

**Data-command grammar wires the new types** (`src/dsl/grammar/data.rs`):
- `TABLE_NAME_INSERT` / `TABLE_NAME_WRITES` (new): table-name
  slots that set `writes_table: true`. Used by insert / update /
  delete to populate `current_table_columns`.
- `SET_COLUMN` / `FILTER_COLUMN` (new): column-name slots in
  `set col=…` / `where col=…` set `writes_column: true`.
- `INSERT_VALUES_LIST` becomes `DynamicSubgrammar(column_value_list)`.
- `UPDATE_ASSIGNMENT` and `WHERE_CLAUSE` use
  `PER_COLUMN_VALUE = DynamicSubgrammar(current_column_value)`.

**Runtime plumbs schema-with-types** (`src/runtime.rs`):
- `refresh_schema_cache` calls `describe_table` for each table
  and populates `SchemaCache::table_columns` with
  `TableColumn { name, user_type }` entries. Best-effort: a
  `describe_table` miss leaves that table unpopulated and the
  walker falls back to schemaless dispatch.

**App dispatches with schema** (`src/app.rs`):
- `dispatch_dsl` routes through `parse_command_with_schema(&self
  .schema_cache, …)` so live typing/dispatch sees the typed
  slots. The replay path stays schemaless (deferred — replay
  bind-time errors still catch type mismatches).

**Catalog** (`src/friendly/strings/en-US.yaml`, `src/friendly/keys.rs`):
- New `parse.custom.bind_type_mismatch` entry with `{found}` and
  `{expected}` placeholders. Surfaced by the int_slot /
  decimal_slot validators.

Tests:
- 11 new walker-side Phase D tests cover insert / update /
  delete with schemas — typed acceptance per column, decimal
  rejection at int columns, null acceptance at any slot,
  multi-assignment per-column dispatch, schemaless fallback.
- The pre-existing `parse_command(input)` test suite (no
  schema) still passes — the fallback path is behaviour-
  preserving.
- 828 passing total, 0 failing, 1 ignored. Clippy clean.

src/dsl/walker/mod.rs

@@ -152,10 +152,10 @@ pub fn expected_at_input(source: &str) -> Vec<outcome::Expectation> {
 ///   walker's error.
 /// - `(None, None)` when the entry word doesn't match any
 ///   registered command — the router falls through to chumsky.
-pub fn walk(
+pub fn walk<'a>(
     source: &str,
     bound: WalkBound,
-    ctx: &mut WalkContext,
+    ctx: &mut WalkContext<'a>,
 ) -> (Option<WalkResult>, Option<Command>) {
     // Phase A only consumes EndOfInput; Position would slice
     // the source, which is the same operation.
@@ -1165,4 +1165,232 @@ mod tests {
         // schema — schema-listable slot, not a HintMode case.
         assert!(hint_mode_at_input("show data ").is_none());
     }
+
+    // =========================================================
+    // Phase D full — schema-aware value typing.
+    // =========================================================
+
+    use crate::completion::{SchemaCache, TableColumn};
+    use crate::dsl::parser::parse_command_with_schema;
+
+    fn schema_with(table: &str, columns: &[(&str, Type)]) -> SchemaCache {
+        let cols: Vec<TableColumn> = columns
+            .iter()
+            .map(|(n, t)| TableColumn {
+                name: (*n).to_string(),
+                user_type: *t,
+            })
+            .collect();
+        let mut cache = SchemaCache::default();
+        cache.tables.push(table.to_string());
+        for c in &cols {
+            cache.columns.push(c.name.clone());
+        }
+        cache.table_columns.insert(table.to_string(), cols);
+        cache
+    }
+
+    #[test]
+    fn phase_d_insert_with_schema_accepts_typed_values_per_column() {
+        let schema = schema_with(
+            "Customers",
+            &[("id", Type::Serial), ("Name", Type::Text), ("Active", Type::Bool)],
+        );
+        // 3 columns: int, text, bool. Each value matches its slot.
+        let cmd = parse_command_with_schema(
+            "insert into Customers values (1, 'Alice', true)",
+            &schema,
+        )
+        .expect("parse");
+        match cmd {
+            Command::Insert { table, values, .. } => {
+                assert_eq!(table, "Customers");
+                assert_eq!(values.len(), 3);
+            }
+            other => panic!("expected Insert, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn phase_d_insert_rejects_decimal_in_int_column() {
+        // The schema has `id` as Int. `3.14` is a Number with a
+        // decimal — the typed `int_slot` validator rejects.
+        let schema = schema_with("T", &[("id", Type::Int)]);
+        let err = parse_command_with_schema("insert into T values (3.14)", &schema)
+            .expect_err("should reject");
+        match err {
+            crate::dsl::ParseError::Invalid { message, .. } => {
+                assert!(
+                    message.contains("integer") || message.contains("3.14"),
+                    "got: {message}"
+                );
+            }
+            other => panic!("expected Invalid, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn phase_d_insert_accepts_null_at_any_column() {
+        // null is the absence sentinel; every typed slot
+        // accepts it.
+        let schema = schema_with(
+            "T",
+            &[("a", Type::Int), ("b", Type::Text), ("c", Type::Bool)],
+        );
+        let cmd = parse_command_with_schema(
+            "insert into T values (null, null, null)",
+            &schema,
+        )
+        .expect("parse");
+        match cmd {
+            Command::Insert { values, .. } => {
+                assert!(values.iter().all(|v| matches!(v, Value::Null)));
+            }
+            other => panic!("expected Insert, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn phase_d_insert_falls_back_when_table_not_in_schema() {
+        // The schema is empty; the walker can't resolve column
+        // info for `Customers`. The DynamicSubgrammar falls
+        // back to the schemaless generic value-literal list and
+        // accepts mixed-shape values as it did pre-Phase-D.
+        let schema = SchemaCache::default();
+        let cmd = parse_command_with_schema(
+            "insert into Customers values (1, 'Alice')",
+            &schema,
+        )
+        .expect("parse — fallback path");
+        match cmd {
+            Command::Insert { values, .. } => assert_eq!(values.len(), 2),
+            other => panic!("expected Insert, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn phase_d_schemaless_parse_command_still_works() {
+        // The pre-Phase-D `parse_command(input)` signature
+        // passes no schema; the DynamicSubgrammar falls back to
+        // the schemaless value-literal list.
+        let cmd = parse("insert into T values (1, 'Alice', null)").expect("parse");
+        match cmd {
+            Command::Insert { values, .. } => assert_eq!(values.len(), 3),
+            other => panic!("expected Insert, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn phase_d_insert_accepts_bool_value_for_bool_column() {
+        let schema = schema_with("T", &[("flag", Type::Bool)]);
+        let cmd = parse_command_with_schema("insert into T values (false)", &schema)
+            .expect("parse");
+        match cmd {
+            Command::Insert { values, .. } => {
+                assert_eq!(values, vec![Value::Bool(false)]);
+            }
+            other => panic!("expected Insert, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn phase_d_update_accepts_text_value_for_text_column() {
+        let schema = schema_with(
+            "Customers",
+            &[("id", Type::Int), ("Email", Type::Text)],
+        );
+        let cmd = parse_command_with_schema(
+            "update Customers set Email='new@b.c' where id=1",
+            &schema,
+        )
+        .expect("parse");
+        match cmd {
+            Command::Update { assignments, .. } => {
+                assert_eq!(assignments.len(), 1);
+                assert_eq!(assignments[0].0, "Email");
+            }
+            other => panic!("expected Update, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn phase_d_update_rejects_decimal_in_int_set_column() {
+        // Email is text; Score is int. Assigning `3.14` to Score
+        // hits the int_slot validator.
+        let schema = schema_with(
+            "T",
+            &[("id", Type::Int), ("Score", Type::Int)],
+        );
+        let err = parse_command_with_schema(
+            "update T set Score=3.14 where id=1",
+            &schema,
+        )
+        .expect_err("should reject");
+        match err {
+            crate::dsl::ParseError::Invalid { message, .. } => {
+                assert!(
+                    message.contains("integer") || message.contains("3.14"),
+                    "got: {message}"
+                );
+            }
+            other => panic!("expected Invalid, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn phase_d_delete_where_uses_typed_column_value() {
+        // `where id=1` — id is Int; `1` matches the int_slot.
+        let schema = schema_with("T", &[("id", Type::Int), ("Name", Type::Text)]);
+        let cmd = parse_command_with_schema("delete from T where id=1", &schema)
+            .expect("parse");
+        match cmd {
+            Command::Delete { .. } => {}
+            other => panic!("expected Delete, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn phase_d_delete_where_rejects_decimal_at_int_column() {
+        // `where id=3.14` — id is Int; the typed slot rejects.
+        let schema = schema_with("T", &[("id", Type::Int)]);
+        let err = parse_command_with_schema("delete from T where id=3.14", &schema)
+            .expect_err("should reject");
+        match err {
+            crate::dsl::ParseError::Invalid { message, .. } => {
+                assert!(
+                    message.contains("integer") || message.contains("3.14"),
+                    "got: {message}"
+                );
+            }
+            other => panic!("expected Invalid, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn phase_d_update_multi_assignment_uses_per_column_types() {
+        let schema = schema_with(
+            "Customers",
+            &[
+                ("id", Type::Int),
+                ("Name", Type::Text),
+                ("Score", Type::Int),
+            ],
+        );
+        // `Score=42` (int slot) and `Name='Alice'` (text slot)
+        // — each value slot dispatches on the column whose
+        // ident matched immediately before.
+        let cmd = parse_command_with_schema(
+            "update Customers set Score=42, Name='Alice' where id=1",
+            &schema,
+        )
+        .expect("parse");
+        match cmd {
+            Command::Update { assignments, .. } => {
+                assert_eq!(assignments.len(), 2);
+                assert_eq!(assignments[0].0, "Score");
+                assert_eq!(assignments[1].0, "Name");
+            }
+            other => panic!("expected Update, got {other:?}"),
+        }
+    }
 }