fix: switch from OpenSSL to rustls for better cross-compilation

- Replace native-tls with rustls in reqwest to avoid OpenSSL dependency
- Remove default features from git2 to reduce dependencies
- Update workflow to remove OpenSSL installation steps
- Simplify Dockerfile by removing OpenSSL packages

This change eliminates OpenSSL as a dependency, which was causing
build failures across all platforms during cross-compilation.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

Author: haasonsaas