feat: fold bot-bottle-orchestrator into bot_bottle/orchestrator subpackage

Moves the orchestrator into bot_bottle/orchestrator/ so one install gets
everything. Entry point is now `python -m bot_bottle.orchestrator run`.

- Add bot_bottle/orchestrator/ with all 14 modules (verbatim move; internal
  imports were already relative, so no changes inside orchestrator modules)
- Rewrite bootstrap.py: remove the lazy bot_bottle import guard, use direct
  relative imports from ..contrib.*
- Add bot_bottle/contrib/forge/base.py: ScopedForge (read-anywhere / write-scoped)
- Add bot_bottle/contrib/gitea/client.py: GiteaClient + GiteaForge (urllib.request only)
- Add bot_bottle/contrib/gitea/forge_state.py: ForgeState + SqliteForgeStateStore
- Add tests/unit/orchestrator/ (82 tests: 63 migrated + 19 new for contrib modules)

Closes #321

bot_bottle/orchestrator/__main__.py

@@ -0,0 +1,51 @@
+"""CLI entry point: `python -m bot_bottle.orchestrator <command>`.
+
+Commands:
+  run      start the webhook server + watchdog + done-signal relay
+  status   print the tracked runs (issue -> slug, status)
+"""
+
+from __future__ import annotations
+
+import argparse
+import sys
+
+from .config import Config
+
+
+def main(argv: list[str] | None = None) -> int:
+    parser = argparse.ArgumentParser(prog="python -m bot_bottle.orchestrator")
+    sub = parser.add_subparsers(dest="command", required=True)
+    sub.add_parser("run", help="start the webhook server, watchdog, and relay")
+    sub.add_parser("status", help="list tracked runs")
+    args = parser.parse_args(argv)
+
+    config = Config.from_env()
+
+    if args.command == "run":
+        from . import bootstrap  # pylint: disable=import-outside-toplevel
+
+        print(
+            f"orchestrator listening on "
+            f"http://{config.webhook_host}:{config.webhook_port}/webhook",
+            file=sys.stderr,
+        )
+        bootstrap.run(config)
+        return 0
+
+    if args.command == "status":
+        from .bootstrap import (  # pylint: disable=import-outside-toplevel
+            BotBottleStateStore,
+        )
+
+        store = BotBottleStateStore(config.db_path)
+        for r in store.all():
+            pr = f"PR#{r.pr_number}" if r.pr_number else "-"
+            print(f"{r.owner}/{r.repo}#{r.issue_number}\t{r.slug}\t{r.status}\t{pr}")
+        return 0
+
+    return 2
+
+
+if __name__ == "__main__":
+    sys.exit(main())