Add plugin helper with agent skill for updating plugins

src/plugin_helper/checker.py

@@ -0,0 +1,66 @@
+from __future__ import annotations
+
+from pathlib import Path
+from typing import Any
+
+from .fsutil import sha256_file
+from .models import Lockfile, Registry
+from .planner import _find_asset
+
+
+def check_lock(
+    *,
+    instance: str,
+    registry: Registry,
+    lockfile: Lockfile,
+    state_root: Path,
+    repo_root: Path,
+) -> dict[str, Any]:
+    entries: list[dict[str, Any]] = []
+    summary = {"ok": 0, "warnings": 0, "errors": 0}
+    for locked in lockfile.plugins:
+        registry_plugin = registry.get(locked.id)
+        strategy = locked.install_strategy or (registry_plugin.install_strategy if registry_plugin else "manual")
+        messages: list[dict[str, str]] = []
+
+        if not registry_plugin:
+            messages.append({"level": "warning", "message": "missing registry entry"})
+        if strategy == "manual":
+            messages.append({"level": "error", "message": "manual install strategy cannot be applied"})
+        if not locked.asset:
+            messages.append({"level": "error", "message": "missing asset"})
+        else:
+            asset_path = _find_asset(locked.asset, state_root, instance, repo_root)
+            if not asset_path:
+                messages.append({"level": "error", "message": "asset not found in downloads or repo assets"})
+            elif locked.sha256 and sha256_file(asset_path) != locked.sha256:
+                messages.append({"level": "error", "message": "asset sha256 mismatch"})
+
+        if any(message["level"] == "error" for message in messages):
+            status = "error"
+            summary["errors"] += 1
+        elif messages:
+            status = "warning"
+            summary["warnings"] += 1
+        else:
+            status = "ok"
+            summary["ok"] += 1
+
+        entries.append(
+            {
+                "id": locked.id,
+                "repo": locked.repo or (registry_plugin.repo if registry_plugin else None),
+                "tag": locked.tag,
+                "asset": locked.asset,
+                "installStrategy": strategy,
+                "status": status,
+                "messages": messages,
+            }
+        )
+
+    return {
+        "instance": instance,
+        "beatSaberVersion": lockfile.beat_saber_version,
+        "summary": summary,
+        "plugins": entries,
+    }