Scope down to local Docker testing, drop Gitea/K3s plumbing for now

This is a pilot project — running it via docker compose locally is enough
for now. Deploy/CI can come back once the project is greenlit for real use.

Also fixes claude invocation: add --strict-mcp-config (verified against
the actual installed claude-code CLI --help) so only agent-news' own MCP
server is loaded, not whatever else might be discoverable in the environment.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

.gitignore

@@ -1,2 +1,3 @@
 .dart_tool/
 build/
+.env