fix: fn::node_info() now handles both record ID formats

Critical bug: fn::node_info() was returning None for valid node IDs because
FROM ONLY $node_id with a string parameter doesn't work correctly in
SurrealDB.

Root cause: SurrealDB requires type::thing() to convert string record IDs
to actual record types for FROM clauses.

Fix: Added smart record ID handling:
- If $node_id contains ':' (e.g., "nodes:uuid") → type::thing($node_id)
- If $node_id is just UUID → type::thing('nodes', $node_id)

This ensures fn::node_info() works with both:
1. Full record IDs from SELECT id queries: "nodes:0002cb76-..."
2. Just UUIDs: "0002cb76-bdea-4461-b489-cc76476ee863"

Without this fix, all graph functions (get_transitive_dependencies,
get_hub_nodes, etc.) were returning None because they all use
fn::node_info() internally.

Author: jruokola

schema/codegraph.surql

@@ -294,6 +294,12 @@ DEFINE INDEX IF NOT EXISTS idx_symbol_embeddings_edge
 -- FUNCTION: node_info (UNCHANGED)
 -- -----------------------------------------------------------------------------
 DEFINE FUNCTION fn::node_info($node_id: string) {
+    LET $record_id = IF string::contains($node_id, ':') THEN
+        type::thing($node_id)
+    ELSE
+        type::thing('nodes', $node_id)
+    END;
+
     LET $res = SELECT
         id,
         name,
@@ -306,7 +312,7 @@ DEFINE FUNCTION fn::node_info($node_id: string) {
             start_line: start_line,
             end_line: end_line
         } AS location
-    FROM ONLY $node_id
+    FROM ONLY $record_id
     LIMIT 1;
 
     RETURN $res[0];