🐛 fix(registries): guard schemaV1 manifest JSON.parse against malformed data

A malformed or missing v1Compatibility from a registry threw a raw
SyntaxError/TypeError that silently dropped the container from the watch
cycle. Fully optional-chain the access and wrap the parse in try/catch
with a descriptive error.

Author: s-b-e-n-s-o-n

app/registries/Registry.test.ts

@@ -745,13 +745,38 @@ describe('getImageManifestDigest', () => {
     );
   });
 
-  test('should handle malformed JSON in schemaVersion 1 v1Compatibility', async () => {
+  test('should throw descriptive error for schemaVersion 1 with malformed (non-JSON) v1Compatibility', async () => {
     const registryMocked = createMockedRegistry();
     registryMocked.callRegistry = () => ({
       schemaVersion: 1,
-      history: [{ v1Compatibility: 'not valid json' }],
+      history: [{ v1Compatibility: 'not valid json {{{' }],
     });
-    await expect(registryMocked.getImageManifestDigest(imageInput())).rejects.toThrow();
+    await expect(registryMocked.getImageManifestDigest(imageInput())).rejects.toThrow(
+      'Failed to parse schemaVersion 1 manifest v1Compatibility',
+    );
+  });
+
+  test('should throw descriptive error for schemaVersion 1 with missing history array', async () => {
+    const registryMocked = createMockedRegistry();
+    registryMocked.callRegistry = () => ({
+      schemaVersion: 1,
+      // history is absent — history?.[0]?.v1Compatibility is undefined, JSON.parse(undefined) throws
+    });
+    await expect(registryMocked.getImageManifestDigest(imageInput())).rejects.toThrow(
+      'Failed to parse schemaVersion 1 manifest v1Compatibility',
+    );
+  });
+
+  test('should throw descriptive error for schemaVersion 1 with missing v1Compatibility field', async () => {
+    const registryMocked = createMockedRegistry();
+    registryMocked.callRegistry = () => ({
+      schemaVersion: 1,
+      history: [{}],
+      // v1Compatibility is absent — JSON.parse(undefined) throws
+    });
+    await expect(registryMocked.getImageManifestDigest(imageInput())).rejects.toThrow(
+      'Failed to parse schemaVersion 1 manifest v1Compatibility',
+    );
   });
 
   test('should gracefully handle blob fetch error for legacy manifest config', async () => {

app/registries/Registry.ts

@@ -106,7 +106,12 @@ function filterManifestByPlatform(
 
 /** Handle schemaVersion 1 manifests (legacy). */
 function handleSchemaV1(response: RegistryManifestResponse): RegistryManifest {
-  const v1Compat = JSON.parse(response.history?.[0].v1Compatibility);
+  let v1Compat: { config?: { Image?: string }; created?: string };
+  try {
+    v1Compat = JSON.parse(response.history?.[0]?.v1Compatibility);
+  } catch {
+    throw new Error('Failed to parse schemaVersion 1 manifest v1Compatibility');
+  }
   return {
     digest: v1Compat.config ? v1Compat.config.Image : undefined,
     created: v1Compat.created,