fix: clarify hook condition handling and add YAML error guidance in templates

- Replace ambiguous "evaluate any condition value" instruction with explicit
  guidance to skip hooks with non-empty conditions, deferring evaluation to
  HookExecutor
- Add instruction to skip hook checking silently if extensions.yml cannot
  be parsed or is invalid

Author: mnriem

templates/commands/implement.md

@@ -139,8 +139,11 @@ Note: This command assumes a complete task breakdown exists in tasks.md. If task
 
 10. **Check for extension hooks**: After completion validation, check if `.specify/extensions.yml` exists in the project root.
     - If it exists, read it and look for entries under the `hooks.after_implement` key
+    - If the YAML cannot be parsed or is invalid, skip hook checking silently and continue normally
     - Filter to only hooks where `enabled: true`
-    - For each remaining hook, evaluate any `condition` value; skip the hook if the condition is not met
+    - For each remaining hook, do **not** attempt to interpret or evaluate hook `condition` expressions:
+      - If the hook has no `condition` field, or it is null/empty, treat the hook as executable
+      - If the hook defines a non-empty `condition`, skip the hook and leave condition evaluation to the HookExecutor implementation
     - For each executable hook, output the following based on its `optional` flag:
       - **Optional hook** (`optional: true`):
         ```

templates/commands/tasks.md

@@ -65,8 +65,11 @@ You **MUST** consider the user input before proceeding (if not empty).
 
 6. **Check for extension hooks**: After tasks.md is generated, check if `.specify/extensions.yml` exists in the project root.
    - If it exists, read it and look for entries under the `hooks.after_tasks` key
+   - If the YAML cannot be parsed or is invalid, skip hook checking silently and continue normally
    - Filter to only hooks where `enabled: true`
-   - For each remaining hook, evaluate any `condition` value; skip the hook if the condition is not met
+   - For each remaining hook, do **not** attempt to interpret or evaluate hook `condition` expressions:
+     - If the hook has no `condition` field, or it is null/empty, treat the hook as executable
+     - If the hook defines a non-empty `condition`, skip the hook and leave condition evaluation to the HookExecutor implementation
    - For each executable hook, output the following based on its `optional` flag:
      - **Optional hook** (`optional: true`):
        ```