Docs: SSH auth, troubleshooting section, changelog, --help examples

[erdemtuna]

Source: codeFindings.md Section 7

Documentation gaps:

1. SSH auth undocumented: Code supports SSH agent auth for git@ URLs but README only mentions tokens. Users may not discover this capability.

2. No troubleshooting section: Common issues (auth failures, cache corruption, agent not detected) would save support time.

3. No changelog: Using auto-generated release notes, but no human-curated CHANGELOG.md for tracking breaking changes and migration guidance.

4. No --help examples: CLI help text is descriptive but does not show usage examples. Most CLI tools include examples in their help output.