fix(audiocpp): replace stale model aliases

backend/engines/audiocpp/bootstrap.py

@@ -226,14 +226,24 @@ def _materialize_gguf_cache_path(model_file: Path) -> Path:
         raise RuntimeError(f"audio.cpp model must be a .gguf file: {model_file}")
 
     def _link(alias: Path) -> Path:
-        try:
-            os.link(resolved, alias)
-        except FileExistsError:
-            if not os.path.samefile(resolved, alias):
+        for attempt in range(2):
+            try:
+                os.link(resolved, alias)
+            except FileExistsError:
+                if (
+                    not alias.is_symlink()
+                    and alias.is_file()
+                    and os.path.samefile(resolved, alias)
+                ):
+                    return alias
+                if attempt == 0 and alias.is_symlink():
+                    alias.unlink()
+                    continue
                 raise RuntimeError(
                     f"audio.cpp model alias points at a different file: {alias}"
                 ) from None
-        return alias
+            return alias
+        raise RuntimeError(f"audio.cpp model alias could not be created: {alias}")
 
     alias = model_file.with_name(
         f".{model_file.stem}-{HF_MODEL_REVISION[:12]}.audiocpp.gguf"

frontend/src/test/backendCrash.http.test.ts

@@ -39,14 +39,15 @@ function okResponse(rec: LastRunCrashRecord | null, acknowledged = false) {
 
 describe('_adaptLastRunCrash — run-sentinel record → CrashMarker shape', () => {
   it('maps the record so the existing crash UI can render it', () => {
-    const marker = _adaptLastRunCrash(record(), false);
+    const sourceRecord = record();
+    const marker = _adaptLastRunCrash(sourceRecord, false);
     expect(marker.exit_code).toBeNull();
     expect(marker.signal).toBeNull();
     // describeCrashExit falls through to exit_desc on a null code+signal.
     expect(describeCrashExit(marker)).toBe('process ended uncleanly (previous run)');
     expect(marker.backend_version).toBe('0.3.23');
     expect(marker.uptime_s).toBe(510);
-    expect(marker.ts).toBe(record().detected_at);
+    expect(marker.ts).toBe(sourceRecord.detected_at);
     expect(marker.acknowledged).toBe(false);
     // The "stderr" evidence carries the last activity + the scrubbed log tail.
     expect(marker.last_stderr).toContain('last activity before the death: transcribe (dub)');

tests/backend/services/test_audiocpp_backend.py

@@ -212,6 +212,24 @@ def test_materialize_rejects_extensionless_model(tmp_path, app_modules):
         bootstrap._materialize_gguf_cache_path(model)
 
 
+def test_materialize_replaces_preexisting_symlink_alias(tmp_path, app_modules):
+    bootstrap = app_modules.bootstrap
+    blob = tmp_path / "content-addressed-blob"
+    blob.write_bytes(b"GGUF test payload")
+    snapshot = tmp_path / "breeze-tts-2-q8_0.gguf"
+    snapshot.symlink_to(blob)
+    alias = snapshot.with_name(
+        f".{snapshot.stem}-{bootstrap.HF_MODEL_REVISION[:12]}.audiocpp.gguf"
+    )
+    alias.symlink_to(blob)
+
+    materialized = bootstrap._materialize_gguf_cache_path(snapshot)
+
+    assert materialized == alias
+    assert not materialized.is_symlink()
+    assert os.path.samefile(materialized, blob)
+
+
 def test_materialize_cross_filesystem_symlink_links_beside_target(
     tmp_path, monkeypatch, app_modules,
 ):
@@ -240,6 +258,7 @@ def test_materialize_cross_filesystem_symlink_links_beside_target(
 
     assert materialized.parent == blob.parent
     assert materialized.suffix == ".gguf"
+    assert not materialized.is_symlink()
     assert os.path.samefile(materialized, blob)