feat: replace global issue lock with keyed persistent store (Closes #443)

Store per remote/org/repo/issue locks under GITEA_ISSUE_LOCK_DIR with
atomic writes and per-session binding. Integrate own-branch adoption for
lock recovery, update worktree-start and cleanup reconcile, and add tests
documenting the ban on manual global lock seeding.

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

tests/test_worktrees.py

@@ -20,33 +20,50 @@ def run(script, *args):
             branch = arg
             break
 
-    lock_file = Path("/tmp/gitea_issue_lock.json")
-    created_lock = False
+    lock_dir_ctx = None
+    extra_env = os.environ.copy()
     if script == "worktree-start" and branch:
         import re
-        import json
+        import tempfile
+        import issue_lock_store
+
         m = re.search(r"issue-(\d+)", branch)
         if not m:
             m = re.search(r"pr-(\d+)", branch)
         issue_num = int(m.group(1)) if m else 999
-        lock_file.write_text(json.dumps({
+        lock_dir_ctx = tempfile.TemporaryDirectory()
+        extra_env["GITEA_ISSUE_LOCK_DIR"] = lock_dir_ctx.name
+        record = {
             "issue_number": issue_num,
             "branch_name": branch,
             "remote": "prgs",
             "org": "Scaled-Tech-Consulting",
-            "repo": "Gitea-Tools"
-        }), encoding="utf-8")
-        created_lock = True
+            "repo": "Gitea-Tools",
+            "worktree_path": "/tmp/test-worktree",
+            "work_lease": {
+                "operation_type": "author_issue_work",
+                "expires_at": "2999-01-01T00:00:00Z",
+            },
+        }
+        path = issue_lock_store.lock_file_path(
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+            issue_number=issue_num,
+            lock_dir=lock_dir_ctx.name,
+        )
+        issue_lock_store.save_lock_file(path, record)
 
     try:
         proc = subprocess.run(
             ["bash", str(SCRIPTS / script), *args],
             capture_output=True, text=True, cwd=str(REPO),
+            env=extra_env,
         )
         return proc.returncode, proc.stdout, proc.stderr
     finally:
-        if created_lock and lock_file.exists():
-            lock_file.unlink()
+        if lock_dir_ctx is not None:
+            lock_dir_ctx.cleanup()
 
 
 class TestWorktreeStart(unittest.TestCase):