feat(aiops): implement ADR-014 Autonomous Code Heal Pipeline

- Added AiderHealExecutor for SSH remote execution of aider-chat
- Added CODE_FIX action_type to AutoHealService
- Added code_exception trigger to Elephant Alpha engine (Traceback log scanning)
- Added 014 playbook migration script

migrations/014_code_fix_playbook.sql

@@ -0,0 +1,11 @@
+-- ADR-014: Aider Code Fix Playbook
+INSERT INTO aiops_playbook (name, description, trigger_pattern, action_type, action_params, is_active)
+VALUES (
+    'Auto-fix Python Runtime exceptions using Aider (ADR-014)',
+    'When Elephant Alpha detects python_exception with tracebacks in logs, trigger CODE_FIX',
+    'python_exception',
+    'CODE_FIX',
+    '{"max_diff_lines": 50, "require_health_check": true, "auto_revert_on_fail": true}'::jsonb,
+    true
+)
+ON CONFLICT DO NOTHING;