fix(git-http): handle relative import when run as top-level script

git_http_backend.py is run as a standalone script in the sidecar
container; relative imports don't work in that context. Fall back
to an absolute import so the module loads correctly either way.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

bot_bottle/git_http_backend.py

@@ -16,7 +16,12 @@ from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
 from pathlib import Path
 from urllib.parse import urlsplit
 
+try:
     from .git_gate import GIT_GATE_TIMEOUT_SECS
+except ImportError:
+    # Running as a top-level script inside the sidecar container
+    # (python3 /app/git_http_backend.py) rather than as part of a package.
+    from git_gate import GIT_GATE_TIMEOUT_SECS  # type: ignore[no-redef]
 
 
 DEFAULT_PORT = 9420