After implementing the health gate, added comprehensive safety measures
to prevent the health checks themselves from becoming a new failure point.
**Problem**: Previous commit added strict health checks but could fail in
edge cases:
- `pct exec` could hang if container stopped/frozen → installer deadlocks
- systemctl/journalctl might not be available → diagnostics fail
- Container access check could fail for transient reasons
- pvecm error detection was fragile (string matching specific messages)
**Solutions Implemented**:
1. **Timeouts on All External Commands** (install.sh:1596,1618)
- `timeout 5` on systemctl checks
- `timeout 10` on pct exec checks
- Prevents installer from hanging indefinitely
2. **Graceful Degradation** (install.sh:1602-1630)
- Check for systemctl/pct availability before using
- Warn if tools missing instead of failing
- Container check is warning-only (may be transient)
- Only fail on critical checks: service running, socket exists
3. **Bypass Flag Support** (install.sh:1589-1594)
- Set `PULSE_SKIP_HEALTH_CHECKS=1` to bypass all checks
- Documented in error messages for troubleshooting
- Allows installation in unsupported environments
4. **Flexible Diagnostics** (install.sh:1640-1647)
- Use journalctl if available, fallback to syslog
- Conditional tool-specific advice
5. **Broader Error Detection** (ssh.go:582-628)
- List of 14 standalone indicators (vs 5 hardcoded checks)
- Case-insensitive matching for localization tolerance
- Permissive strategy: treat any known pattern as standalone
- Handles variations: "no cluster", "IPC", "connection refused", etc.
6. **Enhanced Test Coverage** (ssh_test.go:+35 lines)
- Added 3 new test cases (variation patterns)
- Tests now cover 8 standalone scenarios + 3 negative cases
- All tests pass (11/11)
**Impact**:
- Health gate won't block installation in edge cases
- Better user experience on non-standard setups
- Standalone detection handles more error message variations
- Clear escape hatch for troubleshooting (bypass flag)
**Confidence Level**: High
- All tests pass (bash syntax + Go unit tests)
- Graceful fallbacks for every external command
- Only critical checks are hard failures
- Warnings guide users through validation issues
Related to #571
8e993ea901