Issue: Interactive cluster restore preview showed 'Cannot list databases: exit status 2'
when trying to detect existing databases. This happened because the safety check
functions always used '-h hostname' flag with psql, which breaks peer authentication.
Root cause:
- listPostgresUserDatabases() and checkPostgresDatabaseExists() always included -h flag
- For localhost peer auth, psql should connect via Unix socket (no -h flag)
- Adding -h localhost forces TCP connection which fails with peer authentication
Solution: Match the pattern used throughout the codebase:
- Only add -h flag when host is NOT localhost/127.0.0.1/empty
- For localhost, skip -h flag to use Unix socket
- Set PGPASSWORD only if password is provided
Fixed functions in internal/restore/safety.go:
- listPostgresUserDatabases()
- checkPostgresDatabaseExists()
Now interactive mode correctly shows existing databases count and list when
running as postgres user with peer authentication.
- Auto-detects existing user databases before cluster restore
- Shows count and list (first 5) in preview screen
- Toggle option 'c' to enable cluster cleanup
- Drops all user databases before restore when enabled
- Works for PostgreSQL, MySQL, MariaDB
- Safety warning with database count
- Implements practical disaster recovery workflow
- Fixed type mismatch in disk space calculation (int64 casting)
- Created platform-specific disk space implementations:
* diskspace_unix.go (Linux, macOS, FreeBSD)
* diskspace_windows.go (Windows)
* diskspace_bsd.go (OpenBSD)
* diskspace_netbsd.go (NetBSD fallback)
- All 10 platforms now compile successfully:
✅ Linux (amd64, arm64, armv7)
✅ macOS (Intel, Apple Silicon)
✅ Windows (amd64, arm64)
✅ FreeBSD, OpenBSD, NetBSD
