Production-grade browser extension — X & YouTube Like + Zap

[saiy2k]

PR #87 introduced a basic PoC for like button in x.com for hardcoded authors.

This issue tracks making that extension production-grade: Like + Zap on x.com and YouTube.

Note: Open one focused PR per sub-issue.

Sub-issues

1. Connect to Firebase backend to replace verified-directory.json
2. Zap button
3. Youtube injection
4. Relay configuration in the extension
5. Docs, tests and release