fix(cha): skip CHA expansion for super-dispatch edges

* fix(cha): skip CHA expansion for super-dispatch edges in runChaPostPass and runPostNativeCha

When a method calls super.method(), the resolver creates an edge from the
subclass method to the parent class method (e.g. PostMixin.m → A.m).
runChaPostPass and runPostNativeCha then incorrectly CHA-expanded this edge
to all sibling subclasses of A (e.g. B from other files that also extend A),
producing false PostMixin.m → B.m edges across unrelated files.

Fix: before BFS-expanding a caller→type.method edge, check whether the
caller's class is itself a direct child of the target type. If so, the edge
was produced by a super.method() call (going up the hierarchy) and must not
be expanded downward to sibling subclasses. This applies to both runChaPostPass
(WASM path) and runPostNativeCha (native orchestrator path), which share the
same CHA expansion loop structure.

Verified by node scripts/parity-compare.mjs --langs jelly-micro: the 6
PostMixin super4 false edges are eliminated; all 3048 tests pass.

* fix(cha): replace heuristic super-dispatch guard with technique-based SQL filter

The direct-child heuristic in runChaPostPass / runPostNativeCha had two
flaws raised in review:

1. False positive: any B.method → A.method edge where B extends A was
   treated as a super-dispatch edge, including typed-parameter calls
   (param: A).foo() from within B.method, suppressing legitimate CHA
   expansion to sibling subclasses.

2. Deep-hierarchy miss: implementors.get(typeName) only returns direct
   children. For D extends C extends B, D is not in implementors.get("B"),
   so the guard failed to fire and the false expansion still occurred.

Fix: tag super-dispatch edges with technique='super-dispatch' at insertion
time (build-edges.ts for the WASM path, runPostNativeThisDispatch for the
native path). The CHA expansion queries in runChaPostPass and
runPostNativeCha then filter these edges out via SQL
(AND e.technique != 'super-dispatch'), eliminating the heuristic entirely.

Add Tiger.ts sibling fixture and a test asserting Lion.speak does not
CHA-expand to Tiger.speak, covering both the fix and the regression.

Impact: 6 functions changed, 6 affected

Author: carlos-alm

src/domain/graph/builder/helpers.ts

@@ -464,14 +464,15 @@ export function runChaPostPass(db: BetterSqlite3Database): number {
 
   const callToMethods = db
     .prepare(
-      `SELECT e.source_id, tgt.name AS method_name
+      `SELECT e.source_id, src.name AS caller_name, tgt.name AS method_name
        FROM edges e
        JOIN nodes tgt ON e.target_id = tgt.id
+       JOIN nodes src ON e.source_id = src.id
        WHERE e.kind = 'calls' AND tgt.kind = 'method'
        AND INSTR(tgt.name, '.') > 0
-       AND (e.technique IS NULL OR e.technique != 'cha')`,
+       AND (e.technique IS NULL OR e.technique != 'super-dispatch')`,
     )
-    .all() as Array<{ source_id: number; method_name: string }>;
+    .all() as Array<{ source_id: number; caller_name: string; method_name: string }>;
 
   const seen = new Set<string>();
   // Scope deduplication to only the source_ids we are about to expand, avoiding

src/domain/graph/builder/stages/build-edges.ts

@@ -748,7 +748,10 @@ function buildChaPostPass(
             : computeConfidence(relPath, t.file, null) - CHA_DISPATCH_PENALTY;
           if (conf > 0) {
             seenByPair.add(edgeKey);
-            allEdgeRows.push([caller.id, t.id, 'calls', conf, 0, 'cha']);
+            // Tag super-dispatch edges distinctly so runChaPostPass can exclude them
+            // from further CHA expansion (super calls are not virtual dispatch).
+            const technique = call.receiver === 'super' ? 'super-dispatch' : 'cha';
+            allEdgeRows.push([caller.id, t.id, 'calls', conf, 0, technique]);
           }
         }
       }

src/domain/graph/builder/stages/native-orchestrator.ts

@@ -572,26 +572,37 @@ function runPostNativeCha(
   // incremental role reclassification; confidence uses CHA_TYPED_DISPATCH_CONFIDENCE matching runChaPostPass.
   // When scopeToChangedFiles is true, restrict to call sites in the changed files
   // (safe because no hierarchy or RTA evidence changed outside those files).
-  let callToMethods: Array<{ source_id: number; method_name: string; caller_file: string | null }>;
+  let callToMethods: Array<{
+    source_id: number;
+    caller_name: string;
+    method_name: string;
+    caller_file: string | null;
+  }>;
   if (scopeToChangedFiles && changedFiles && changedFiles.length > 0) {
     const CHUNK_SIZE = 500;
-    const rows: Array<{ source_id: number; method_name: string; caller_file: string | null }> = [];
+    const rows: Array<{
+      source_id: number;
+      caller_name: string;
+      method_name: string;
+      caller_file: string | null;
+    }> = [];
     for (let i = 0; i < changedFiles.length; i += CHUNK_SIZE) {
       const chunk = changedFiles.slice(i, i + CHUNK_SIZE);
       const ph = chunk.map(() => '?').join(',');
       const chunkRows = db
         .prepare(
-          `SELECT e.source_id, tgt.name AS method_name, src.file AS caller_file
+          `SELECT e.source_id, src.name AS caller_name, tgt.name AS method_name, src.file AS caller_file
            FROM edges e
            JOIN nodes tgt ON e.target_id = tgt.id
            JOIN nodes src ON e.source_id = src.id
            WHERE e.kind = 'calls' AND tgt.kind = 'method'
            AND INSTR(tgt.name, '.') > 0
-           AND (e.technique IS NULL OR e.technique != 'cha')
+           AND (e.technique IS NULL OR e.technique != 'super-dispatch')
            AND src.file IN (${ph})`,
         )
         .all(...chunk) as Array<{
         source_id: number;
+        caller_name: string;
         method_name: string;
         caller_file: string | null;
       }>;
@@ -601,15 +612,20 @@ function runPostNativeCha(
   } else {
     callToMethods = db
       .prepare(`
-        SELECT e.source_id, tgt.name AS method_name, src.file AS caller_file
+        SELECT e.source_id, src.name AS caller_name, tgt.name AS method_name, src.file AS caller_file
         FROM edges e
         JOIN nodes tgt ON e.target_id = tgt.id
         JOIN nodes src ON e.source_id = src.id
         WHERE e.kind = 'calls' AND tgt.kind = 'method'
         AND INSTR(tgt.name, '.') > 0
-        AND (e.technique IS NULL OR e.technique != 'cha')
+        AND (e.technique IS NULL OR e.technique != 'super-dispatch')
       `)
-      .all() as Array<{ source_id: number; method_name: string; caller_file: string | null }>;
+      .all() as Array<{
+      source_id: number;
+      caller_name: string;
+      method_name: string;
+      caller_file: string | null;
+    }>;
   }
 
   // Seed seen-pairs only from the source_ids we'll be expanding — avoids loading every
@@ -950,7 +966,10 @@ async function runPostNativeThisDispatch(
         seen.add(key);
         const conf = computeConfidence(relPath, t.file, null) - CHA_DISPATCH_PENALTY;
         if (conf <= 0) continue;
-        newEdges.push([callerRow.id, t.id, 'calls', conf, 0, 'cha']);
+        // Tag super-dispatch edges distinctly so runPostNativeCha can exclude them
+        // from further CHA expansion (super calls are not virtual dispatch).
+        const technique = call.receiver === 'super' ? 'super-dispatch' : 'cha';
+        newEdges.push([callerRow.id, t.id, 'calls', conf, 0, technique]);
         targetIds.add(t.id);
         affectedFiles.add(relPath);
         if (t.file) affectedFiles.add(t.file);

tests/fixtures/cha-dispatch/Tiger.ts

@@ -0,0 +1,7 @@
+import { Animal } from './Animal.js';
+
+export class Tiger extends Animal {
+  speak(): string {
+    return 'ROAR';
+  }
+}

tests/integration/phase-8.5-cha-dispatch.test.ts

@@ -148,6 +148,19 @@ describe.each(ENGINES)('Phase 8.5 CHA dispatch (%s)', (engine) => {
     ).toBeDefined();
   });
 
+  it('super-dispatch: does NOT CHA-expand Lion.speak to sibling Tiger.speak', () => {
+    // Tiger is also a subclass of Animal (sibling to Lion). A super.speak() call
+    // in Lion.speak goes to Animal.speak — it must NOT be CHA-expanded to
+    // Tiger.speak (a sibling), which Lion would never invoke.
+    const edge = callEdges.find(
+      (e) => e.caller_name === 'Lion.speak' && e.callee_name === 'Tiger.speak',
+    );
+    expect(
+      edge,
+      `Expected NO Lion.speak → Tiger.speak edge (super-dispatch must not expand to sibling subclasses).\nActual edges:\n${JSON.stringify(callEdges, null, 2)}`,
+    ).toBeUndefined();
+  });
+
   // ── transitive multi-level CHA (issue #1311) ───────────────────────────
   // Hierarchy: IJob → AbstractJob (non-instantiated) → PrintJob / ScanJob
   // resolveChaTargets must BFS through AbstractJob to reach the concrete types.