fix: use record cast for fn::node_info() parameter handling

Fixed fn::node_info() to properly handle SurrealDB record IDs using
<record> type casting instead of type::thing() construction.

Root cause: SurrealDB stores IDs as record types (nodes:⟨uuid⟩) and when
passed as string parameters, they need to be cast back to record type for
FROM clauses to work.

Fix:
- Build full record ID string: "nodes:uuid" (handles both formats)
- Use <record> cast: FROM ONLY <record> $full_id
- Return $res directly (FROM ONLY returns single object, not array)

This handles:
1. Full record ID string: "nodes:0002cb76-..." → used as-is
2. Just UUID: "0002cb76-..." → prepended with "nodes:"
3. Record cast: <record> converts string to proper Thing type

Test with:
  SELECT fn::node_info('0002cb76-bdea-4461-b489-cc76476ee863');
  SELECT fn::node_info('nodes:0002cb76-bdea-4461-b489-cc76476ee863');

Author: jruokola

schema/codegraph.surql

@@ -294,12 +294,14 @@ 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)
+    -- Build full record ID string ("nodes:uuid" format)
+    LET $full_id = IF string::starts_with($node_id, 'nodes:') THEN
+        $node_id
     ELSE
-        type::thing('nodes', $node_id)
+        string::concat('nodes:', $node_id)
     END;
 
+    -- Cast string to record and query
     LET $res = SELECT
         id,
         name,
@@ -312,10 +314,9 @@ DEFINE FUNCTION fn::node_info($node_id: string) {
             start_line: start_line,
             end_line: end_line
         } AS location
-    FROM ONLY $record_id
-    LIMIT 1;
+    FROM ONLY <record> $full_id;
 
-    RETURN $res[0];
+    RETURN $res;
 };
 
 -- -----------------------------------------------------------------------------