Add plugin update and install reporting

src/plugin_helper/github.py

@@ -0,0 +1,22 @@
+from __future__ import annotations
+
+import json
+import os
+from typing import Any
+from urllib.request import Request, urlopen
+
+
+def fetch_releases(repo: str) -> list[dict[str, Any]]:
+    token = os.environ.get("GITHUB_TOKEN")
+    headers = {
+        "Accept": "application/vnd.github+json",
+        "User-Agent": "plugin-helper",
+    }
+    if token:
+        headers["Authorization"] = f"Bearer {token}"
+    request = Request(f"https://api.github.com/repos/{repo}/releases", headers=headers)
+    with urlopen(request, timeout=20) as response:
+        data = json.loads(response.read().decode("utf-8"))
+    if not isinstance(data, list):
+        raise ValueError(f"unexpected GitHub releases response for {repo}")
+    return data