Matrix: create table, DDL, and app-command coverage

55 tests covering create table, drop column, drop relationship
(endpoints + by-name), add relationship, rename/change column, and
all app-lifecycle commands. The drop-column and relationship tests
drove the §2.2 writes_table fix in the previous commit.

Documents one UX wrinkle as a flagged finding: partial entry words
(`qu`) classify as DefiniteErrorAt — same as unknown commands —
because the walker only engages on a complete entry word.

859 baseline -> 989 passing; 1 ignored (pre-existing doc-test).

tests/typing_surface/create_table.rs

@@ -1 +1,135 @@
-//! Submodule stub — populated in subsequent tasks.
+//! Matrix coverage for `create table T with pk [<col>:<type>[, ...]]`
+//! (ADR-0005, ADR-0009).
+
+use crate::typing_surface::*;
+use rdbms_playground::input_render::{AmbientHint, InputState};
+
+#[test]
+fn after_create_expects_table() {
+    let schema = schema_empty();
+    let a = assess_at_end("create ", &schema);
+    assert!(matches!(a.state, InputState::IncompleteAtEof));
+    assert_candidate_present(&a, &["table"]);
+    crate::snap!("after_create", a);
+}
+
+#[test]
+fn after_table_keyword_offers_no_candidates_for_new_name() {
+    // The table-name slot is IdentSource::NewName — the user
+    // invents the name, so no candidates from the schema. The
+    // hint resolver surfaces a ForceProse "Type a name [then ...]"
+    // affordance instead.
+    let schema = schema_empty();
+    let a = assess_at_end("create table ", &schema);
+    assert!(matches!(a.state, InputState::IncompleteAtEof));
+    assert!(
+        matches!(&a.hint, Some(AmbientHint::Prose(_))),
+        "expected Prose at NewName slot, got {:?}",
+        a.hint,
+    );
+    crate::snap!("after_table_keyword", a);
+}
+
+#[test]
+fn after_new_table_name_expects_with() {
+    let schema = schema_empty();
+    let a = assess_at_end("create table Customers ", &schema);
+    assert!(matches!(a.state, InputState::IncompleteAtEof));
+    assert_candidate_present(&a, &["with"]);
+    crate::snap!("after_new_table_name", a);
+}
+
+#[test]
+fn after_with_expects_pk() {
+    let schema = schema_empty();
+    let a = assess_at_end("create table Customers with ", &schema);
+    assert!(matches!(a.state, InputState::IncompleteAtEof));
+    assert_candidate_present(&a, &["pk"]);
+    crate::snap!("after_with", a);
+}
+
+#[test]
+fn create_table_with_pk_default_parses() {
+    let schema = schema_empty();
+    let a = assess_at_end("create table Customers with pk", &schema);
+    assert!(matches!(a.state, InputState::Valid));
+    assert_eq!(a.parse_result.as_deref(), Ok("CreateTable"));
+    crate::snap!("with_pk_default", a);
+}
+
+#[test]
+fn after_pk_word_does_not_re_offer_pk() {
+    // Handoff-12 regression: at the cursor position right after
+    // `with pk`, the completion engine must NOT re-offer `pk` as
+    // a candidate. The full input parses and the partial-prefix
+    // filter drops it.
+    let schema = schema_empty();
+    let a = assess_at_end("create table Customers with pk", &schema);
+    let cands = completion_candidate_texts(&a);
+    assert!(
+        !cands.contains(&"pk".to_string()),
+        "should NOT re-suggest `pk` (handoff-12 regression), got: {cands:?}",
+    );
+}
+
+#[test]
+fn after_pk_space_with_col_name_typed_expects_colon() {
+    let schema = schema_empty();
+    let a = assess_at_end("create table Customers with pk Code", &schema);
+    assert!(matches!(a.state, InputState::IncompleteAtEof));
+    crate::snap!("after_col_name", a);
+}
+
+#[test]
+fn after_colon_expects_type_candidates() {
+    let schema = schema_empty();
+    let a = assess_at_end(
+        "create table Customers with pk Code:",
+        &schema,
+    );
+    assert!(matches!(a.state, InputState::IncompleteAtEof));
+    assert_candidate_present(
+        &a,
+        &["text", "int", "serial", "shortid", "bool"],
+    );
+    crate::snap!("after_colon", a);
+}
+
+#[test]
+fn create_table_with_explicit_pk_parses() {
+    let schema = schema_empty();
+    let a = assess_at_end(
+        "create table Customers with pk Code:text",
+        &schema,
+    );
+    assert!(matches!(a.state, InputState::Valid));
+    crate::snap!("with_explicit_pk", a);
+}
+
+#[test]
+fn create_table_with_compound_pk_parses() {
+    let schema = schema_empty();
+    let a = assess_at_end(
+        "create table Memberships with pk UserId:int, GroupId:int",
+        &schema,
+    );
+    assert!(matches!(a.state, InputState::Valid));
+    crate::snap!("with_compound_pk", a);
+}
+
+#[test]
+fn create_table_without_with_pk_is_incomplete() {
+    // Tables need at least one column (parse.custom.
+    // create_table_needs_pk) — submitting `create table T`
+    // alone is rejected. Classification depends on whether the
+    // walker treats `with pk` as required or optional at this
+    // position.
+    let schema = schema_empty();
+    let a = assess_at_end("create table Customers", &schema);
+    assert!(
+        !matches!(a.state, InputState::Valid),
+        "create table without `with pk` must not be Valid, got {:?}",
+        a.state,
+    );
+    crate::snap!("no_with_pk", a);
+}