fix(extraction): preserve symbols with colliding same-line IDs (#1349) (#2030)

Same-kind, same-name declarations on one line shared an ID and silently overwrote each other in SQLite.
Use per-extraction collision tracking to append a UTF-16 column only to later distinct declarations.
Apply the same rule across wasm, Rust language walkers, Liquid, and CFML while preserving file IDs and edge endpoints.
Add persistence, call-edge, identity-vector, and Unicode parity regressions.

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

codegraph-kernel/src/python.rs

@@ -141,6 +141,7 @@ pub struct Walker<'t> {
     file_path: &'t str,
     line_starts: Vec<usize>,
     arena: Arena,
+    node_id_allocator: ids::NodeIdAllocator,
     tables: Tables,
     stack: Vec<Scope>,
     node_ids: Vec<String>,
@@ -171,6 +172,7 @@ pub fn extract(file_path: &str, source: &str) -> Result<EmitOut, String> {
         file_path,
         line_starts: util::line_starts(source),
         arena: Arena::default(),
+        node_id_allocator: ids::NodeIdAllocator::default(),
         tables: Tables::default(),
         stack: Vec::new(),
         node_ids: Vec::new(),
@@ -276,7 +278,8 @@ impl<'t> Walker<'t> {
             return None;
         }
         let start_line = self.line_of(node);
-        let id = ids::node_id(self.file_path, kind, name, start_line);
+        let column = self.col_of(node);
+        let id = self.node_id_allocator.generate(self.file_path, kind, name, start_line, column);
         let end_line = node.end_position().row as u32 + 1;
 
         let qualified = {