feat: add codex hook format and install_codex_hooks

src/agent_learner/adapters/codex.py

@@ -3,7 +3,7 @@
 import shlex
 from pathlib import Path
 
-from .common import append_lines_if_missing, ensure_dir, merge_json_file, write_text
+from .common import append_lines_if_missing, ensure_dir, merge_json_file, upsert_hook, write_text
 from agent_learner.core.storage import migrate_legacy_learning_assets
 
 
@@ -336,3 +336,20 @@ def install_codex_adapter_with_scope(target_root: Path, *, scope: str = "project
     if scope == "project":
         written.extend(migrate_legacy_learning_assets(target_root))
     return written
+
+
+# ---------------------------------------------------------------------------
+# Phase 2: lightweight hook installer (mirrors claude adapter pattern)
+# ---------------------------------------------------------------------------
+
+_CODEX_HOOK_COMMAND = "agent-learner process --adapter codex --auto"
+
+
+def install_codex_hooks(project_root: Path, *, scope: str = "project") -> Path:
+    """Install agent-learner Stop hook into .codex/hooks.json.
+
+    Idempotent: updates existing agent-learner hook if present.
+    Preserves other Stop hooks.
+    """
+    settings_path = project_root / ".codex" / "hooks.json"
+    return upsert_hook(settings_path, "Stop", _CODEX_HOOK_COMMAND, hook_format="codex")

src/agent_learner/adapters/common.py

@@ -79,6 +79,10 @@ def _make_hook_entry(command: str, *, hook_format: str) -> dict:
             "matcher": ".*",
             "hooks": [{"type": "command", "command": command}],
         }
+    if hook_format == "codex":
+        return {
+            "hooks": [{"type": "command", "command": command}],
+        }
     return {"command": command}