chore: ignore deployment-local compose override and connector record

From the PR description

Summary

Ignore two files a self-hosted install leaves in the repository root, so a routine git add -A on a server cannot commit one deployment's local wiring into the shared repository.

Changes

• .gitignore: add docker-compose.override.yml and .microsoft365-deployment.json.

Why

Neither file is tracked, and neither was ignored. On a live self-hosted install both sit in the repository root next to the compose files:

• docker-compose.override.yml - the compose override that pins that install's ports and image tags.
• .microsoft365-deployment.json - written when the Microsoft 365 connector is set up; it records image ids, source checksums, test results and the connector's orgId.

They describe one deployment, not the project, so committing them is noise at best and leaks install topology at worst. CONTRIBUTING.md already asks contributors not to commit local .env files; these belong in the same category.

Testing

On a live install with both files present:

• git check-ignore -v .microsoft365-deployment.json docker-compose.override.yml - both now match the new rules.
• Staged git add -A into a throwaway index and diffed it against origin/main: neither file appears any more; before the change both did.
• Both files are untracked (git ls-files --error-unmatch fails for them), so the new rules take effect without needing git rm --cached.

No code paths changed.

🤖 Generated with Claude Code

https://claude.ai/code/session_01CRjeWGpYBpsp2ntUbDeoKP