This PR includes three main improvements:
1. Tailscale Binary Detection with Fallback Strategies
- Added findTailscaleBinary() with multi-strategy detection:
* PATH lookup via 'which' command
* Known macOS app path (/Applications/Tailscale.app/Contents/MacOS/Tailscale)
* find /Applications for Tailscale.app
* locate database lookup
- Added getTailscaleBinary() with caching
- Updated all Tailscale operations to use detected binary
- Added TUI warning when Tailscale binary not found for serve/funnel modes
2. Custom Gateway IP Binding with Fallback
- New bind mode "custom" allowing user-specified IP with fallback to 0.0.0.0
- Removed "tailnet" mode (folded into "auto")
- All modes now support graceful fallback: custom (if fail → 0.0.0.0), loopback (127.0.0.1 → 0.0.0.0), auto (tailnet → 0.0.0.0), lan (0.0.0.0)
- Added customBindHost config option for custom bind mode
- Added canBindTo() helper to test IP availability before binding
- Updated configure and onboarding wizards with new bind mode options
3. Health Probe Password Auth Fix
- Gateway probe now tries both new and old passwords
- Fixes issue where password change fails health check if gateway hasn't restarted yet
- Uses nextConfig password first, falls back to baseConfig password if needed
Files changed:
- src/infra/tailscale.ts: Binary detection + caching
- src/gateway/net.ts: IP binding with fallback logic
- src/config/types.ts: BridgeBindMode type + customBindHost field
- src/commands/configure.ts: Health probe dual-password try + Tailscale detection warning + bind mode UI
- src/wizard/onboarding.ts: Tailscale detection warning + bind mode UI
- src/gateway/server.ts: Use new resolveGatewayBindHost
- src/gateway/call.ts: Updated preferTailnet logic (removed "tailnet" mode)
- src/commands/onboard-types.ts: Updated GatewayBind type
- src/commands/onboard-helpers.ts: resolveControlUiLinks updated
- src/cli/*.ts: Updated bind mode casts
- src/gateway/call.test.ts: Removed "tailnet" mode test
When readConfigFileSnapshot encounters validation errors, it now:
1. Returns the resolved config data instead of empty object
2. Uses passthrough() on main schema to preserve unknown fields
This prevents config loss when:
- User has custom/unknown fields
- Legacy config issues are detected but config is otherwise valid
- Zod schema does not recognize newer fields
Fixes config being overwritten with empty object on validation failure.
