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/dsl/grammar/sql_delete.rs

@@ -82,7 +82,14 @@ mod tests {
         let mut ctx = WalkContext::new();
         let mut path = MatchedPath::new();
         let mut per_byte = Vec::new();
-        match walk_node(input, 0, &SQL_DELETE_SHAPE, &mut ctx, &mut path, &mut per_byte) {
+        match walk_node(
+            input,
+            0,
+            &SQL_DELETE_SHAPE,
+            &mut ctx,
+            &mut path,
+            &mut per_byte,
+        ) {
             NodeWalkResult::Matched { end, .. } => input[end..].trim().is_empty(),
             _ => false,
         }
@@ -93,7 +100,10 @@ mod tests {
     }
 
     fn bad(input: &str) {
-        assert!(!walks(input), "{input:?} should NOT walk as a complete DELETE tail");
+        assert!(
+            !walks(input),
+            "{input:?} should NOT walk as a complete DELETE tail"
+        );
     }
 
     #[test]