style: format the whole tree with cargo fmt (stock defaults, #35)

One-time, mechanical reformat — no functional changes. The tree was not
rustfmt-clean (~1800 hunks across ~100 files); this brings it to stock
`cargo fmt` defaults so a `cargo fmt --check` CI gate can follow.
Behaviour-preserving: 2509 pass / 0 fail / 1 ignored (unchanged baseline),
clippy clean. A .git-blame-ignore-revs entry follows so `git blame`
skips this commit.

src/friendly/keys.rs

@@ -41,8 +41,14 @@ pub const KEYS_AND_PLACEHOLDERS: &[(&str, &[&str])] = &[
     ("diagnostic.alias_used_as_column", &["name"]),
     ("diagnostic.ambiguous_column", &["column", "qualifiers"]),
     ("diagnostic.auto_column_overridden", &["column", "type"]),
-    ("diagnostic.compound_arity_mismatch", &["op", "left_n", "right_n"]),
-    ("diagnostic.cte_arity_mismatch", &["cte", "declared", "actual"]),
+    (
+        "diagnostic.compound_arity_mismatch",
+        &["op", "left_n", "right_n"],
+    ),
+    (
+        "diagnostic.cte_arity_mismatch",
+        &["cte", "declared", "actual"],
+    ),
     ("diagnostic.duplicate_cte", &["name"]),
     ("diagnostic.eq_null", &[]),
     ("diagnostic.insert_arity_mismatch", &["expected", "actual"]),
@@ -63,7 +69,10 @@ pub const KEYS_AND_PLACEHOLDERS: &[(&str, &[&str])] = &[
     ),
     ("diagnostic.not_null_missing", &["column"]),
     ("diagnostic.like_numeric", &["column", "type"]),
-    ("diagnostic.projection_alias_misplaced", &["alias", "clause"]),
+    (
+        "diagnostic.projection_alias_misplaced",
+        &["alias", "clause"],
+    ),
     ("diagnostic.table_used_as_column", &["name"]),
     ("diagnostic.type_mismatch", &["column", "type"]),
     ("diagnostic.unknown_column", &["name", "table"]),
@@ -149,10 +158,7 @@ pub const KEYS_AND_PLACEHOLDERS: &[(&str, &[&str])] = &[
         "error.type_mismatch.change_column.headline",
         &["table", "column", "src_type", "target_type"],
     ),
-    (
-        "error.type_mismatch.change_column.hint",
-        &["target_type"],
-    ),
+    ("error.type_mismatch.change_column.hint", &["target_type"]),
     (
         "error.type_mismatch.insert.headline",
         &["value", "expected_type"],
@@ -219,10 +225,7 @@ pub const KEYS_AND_PLACEHOLDERS: &[(&str, &[&str])] = &[
     ("help.data.explain", &[]),
     // ---- Hint panel ambient typing assistance (ADR-0022 §6) ----
     ("hint.ambient_complete", &[]),
-    (
-        "hint.ambient_error_with_usage",
-        &["message", "usage"],
-    ),
+    ("hint.ambient_error_with_usage", &["message", "usage"]),
     ("hint.ambient_expected", &["expected"]),
     ("hint.getting_started", &[]),
     ("hint.block.heading", &[]),
@@ -404,10 +407,7 @@ pub const KEYS_AND_PLACEHOLDERS: &[(&str, &[&str])] = &[
     ("hint.cmd.explain_sql.what", &[]),
     ("hint.cmd.explain_sql.example", &[]),
     ("hint.cmd.explain_sql.concept", &[]),
-    (
-        "hint.ambient_invalid_ident",
-        &["kind", "found"],
-    ),
+    ("hint.ambient_invalid_ident", &["kind", "found"]),
     ("hint.ambient_typing_name", &[]),
     // Issue #4: introduce the advanced-mode CREATE TABLE element
     // slot (`create table T (`) so the otherwise-invisible
@@ -415,10 +415,7 @@ pub const KEYS_AND_PLACEHOLDERS: &[(&str, &[&str])] = &[
     ("hint.create_table_element", &[]),
     ("hint.seed_count", &[]),
     ("hint.value_literal_slot", &[]),
-    (
-        "hint.ambient_typing_name_then",
-        &["next"],
-    ),
+    ("hint.ambient_typing_name_then", &["next"]),
     // Per-column-type value-slot hints (ADR-0024 §Phase D).
     ("hint.value_slot_blob", &[]),
     ("hint.value_slot_bool", &[]),
@@ -441,7 +438,10 @@ pub const KEYS_AND_PLACEHOLDERS: &[(&str, &[&str])] = &[
     ("parse.custom.alter_named_unique", &[]),
     ("parse.custom.bind_type_mismatch", &["found", "expected"]),
     ("parse.custom.change_column_flags_exclusive", &[]),
-    ("parse.custom.constraint_redundant_on_pk", &["column", "constraint"]),
+    (
+        "parse.custom.constraint_redundant_on_pk",
+        &["column", "constraint"],
+    ),
     ("parse.custom.create_table_needs_pk", &[]),
     ("parse.custom.expression_too_deep", &[]),
     ("parse.custom.insert_form_a_missing_values", &["columns"]),
@@ -576,10 +576,7 @@ pub const KEYS_AND_PLACEHOLDERS: &[(&str, &[&str])] = &[
         &["table", "col_count", "col_list", "supplied", "non_auto_csv"],
     ),
     ("select.internal_table", &["table"]),
-    (
-        "cli.invalid_value",
-        &["flag", "value", "expected"],
-    ),
+    ("cli.invalid_value", &["flag", "value", "expected"]),
     ("cli.missing_value", &["flag"]),
     ("cli.multiple_paths", &["first", "second"]),
     ("cli.resume_with_path", &[]),
@@ -867,8 +864,7 @@ mod tests {
             }
         }
 
-        let declared: HashSet<&str> =
-            KEYS_AND_PLACEHOLDERS.iter().map(|(k, _)| *k).collect();
+        let declared: HashSet<&str> = KEYS_AND_PLACEHOLDERS.iter().map(|(k, _)| *k).collect();
         for key in cat.keys() {
             if key.starts_with("_test.") {
                 continue;
@@ -890,9 +886,8 @@ mod tests {
     /// Mirror of `tests/engine_vocabulary_audit.rs::FORBIDDEN`,
     /// duplicated here so the catalog validator is self-contained
     /// (no dependency on the integration-test binary).
-    const FORBIDDEN_ENGINE_VOCABULARY: &[&str] = &[
-        "SQLite", "sqlite", "rusqlite", "STRICT", "PRAGMA",
-    ];
+    const FORBIDDEN_ENGINE_VOCABULARY: &[&str] =
+        &["SQLite", "sqlite", "rusqlite", "STRICT", "PRAGMA"];
 
     /// Detect a `{name:...}` format-specifier placeholder.
     /// Doubled braces `{{` / `}}` are escapes — must skip them.