Add WireGuard VPN with random /31 subnet isolation (v0.40.0)

- Add embedded WireGuard VPN server using wireguard-go + netstack
- Implement deterministic /31 subnet allocation from seed + sequence
- Use Badger's built-in Sequence for atomic counter allocation
- Add NIP-46 bunker server for remote signing over VPN
- Add revoked key tracking and access audit logging for users
- Add Bunker tab to web UI with WireGuard/bunker QR codes
- Support key regeneration with old keypair archiving

New environment variables:
- ORLY_WG_ENABLED: Enable WireGuard VPN server
- ORLY_WG_PORT: UDP port for WireGuard (default 51820)
- ORLY_WG_ENDPOINT: Public endpoint for WireGuard
- ORLY_WG_NETWORK: Base network for subnet pool (default 10.0.0.0/8)
- ORLY_BUNKER_ENABLED: Enable NIP-46 bunker
- ORLY_BUNKER_PORT: WebSocket port for bunker (default 3335)

Files added:
- pkg/wireguard/: WireGuard server, keygen, subnet pool, errors
- pkg/bunker/: NIP-46 bunker server and session handling
- pkg/database/wireguard.go: Peer storage with audit logging
- app/handle-wireguard.go: API endpoints for config/regenerate/audit
- app/wireguard-helpers.go: Key derivation helpers
- app/web/src/BunkerView.svelte: Bunker UI with QR codes

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

go.mod

@@ -49,6 +49,7 @@ require (
 	github.com/felixge/fgprof v0.9.5 // indirect
 	github.com/go-logr/logr v1.4.3 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
+	github.com/google/btree v1.1.2 // indirect
 	github.com/google/flatbuffers v25.9.23+incompatible // indirect
 	github.com/google/pprof v0.0.0-20251007162407-5df77e3f7d1d // indirect
 	github.com/josharian/intern v1.0.0 // indirect
@@ -78,9 +79,13 @@ require (
 	golang.org/x/sync v0.19.0 // indirect
 	golang.org/x/sys v0.39.0 // indirect
 	golang.org/x/text v0.32.0 // indirect
+	golang.org/x/time v0.7.0 // indirect
 	golang.org/x/tools v0.40.0 // indirect
+	golang.zx2c4.com/wintun v0.0.0-20230126152724-0fa3db229ce2 // indirect
+	golang.zx2c4.com/wireguard v0.0.0-20250521234502-f333402bd9cb // indirect
 	google.golang.org/protobuf v1.36.10 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
+	gvisor.dev/gvisor v0.0.0-20250503011706-39ed1f5ac29c // indirect
 	p256k1.mleku.dev v1.0.3 // indirect
 )