Finish Phase 6: Push frontend, WebAuthn frontend, OpenAPI/Swagger

Frontend:
- stores/push.ts: fixed VAPID key endpoint, added checkSubscription, proper subscription format
- UserSettings.tsx: added [ENABLE PUSH] toggle and [REGISTER PASSKEY] button
- LoginForm.tsx: added [SIGN IN WITH PASSKEY] button

Backend:
- cmd/server/main.go: added Swagger annotations, /docs/* route
- docs/: generated swagger.json, swagger.yaml, docs.go
- Makefile: added docs target for swag init

go.mod

@@ -25,6 +25,7 @@ require (
 	buf.build/go/protovalidate v1.2.0 // indirect
 	buf.build/go/protoyaml v0.7.0 // indirect
 	cel.dev/expr v0.25.2 // indirect
+	github.com/KyleBanks/depth v1.2.1 // indirect
 	github.com/antlr4-go/antlr/v4 v4.13.1 // indirect
 	github.com/atotto/clipboard v0.1.4 // indirect
 	github.com/aymanbagabas/go-osc52/v2 v2.0.1 // indirect
@@ -47,6 +48,10 @@ require (
 	github.com/gammazero/deque v1.2.1 // indirect
 	github.com/go-logr/logr v1.4.3 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
+	github.com/go-openapi/jsonpointer v0.19.5 // indirect
+	github.com/go-openapi/jsonreference v0.20.0 // indirect
+	github.com/go-openapi/spec v0.20.6 // indirect
+	github.com/go-openapi/swag v0.19.15 // indirect
 	github.com/go-viper/mapstructure/v2 v2.5.0 // indirect
 	github.com/go-webauthn/x v0.2.6 // indirect
 	github.com/golang-jwt/jwt/v5 v5.3.1 // indirect
@@ -55,6 +60,7 @@ require (
 	github.com/jackc/pgpassfile v1.0.0 // indirect
 	github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 // indirect
 	github.com/jackc/puddle/v2 v2.2.2 // indirect
+	github.com/josharian/intern v1.0.0 // indirect
 	github.com/jxskiss/base62 v1.1.0 // indirect
 	github.com/klauspost/compress v1.18.6 // indirect
 	github.com/klauspost/cpuid/v2 v2.3.0 // indirect
@@ -65,6 +71,7 @@ require (
 	github.com/livekit/psrpc v0.7.2 // indirect
 	github.com/lucasb-eyer/go-colorful v1.4.0 // indirect
 	github.com/magefile/mage v1.17.2 // indirect
+	github.com/mailru/easyjson v0.7.6 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/mattn/go-localereader v0.0.1 // indirect
 	github.com/mattn/go-runewidth v0.0.23 // indirect
@@ -102,6 +109,9 @@ require (
 	github.com/redis/go-redis/v9 v9.20.0 // indirect
 	github.com/rivo/uniseg v0.4.7 // indirect
 	github.com/rs/xid v1.6.0 // indirect
+	github.com/swaggo/files v0.0.0-20220610200504-28940afbdbfe // indirect
+	github.com/swaggo/http-swagger v1.3.4 // indirect
+	github.com/swaggo/swag v1.8.1 // indirect
 	github.com/tinylib/msgp v1.6.4 // indirect
 	github.com/twitchtv/twirp v8.1.3+incompatible // indirect
 	github.com/wlynxg/anet v0.0.5 // indirect
@@ -120,9 +130,11 @@ require (
 	golang.org/x/sys v0.46.0 // indirect
 	golang.org/x/text v0.38.0 // indirect
 	golang.org/x/time v0.15.0 // indirect
+	golang.org/x/tools v0.45.0 // indirect
 	google.golang.org/genproto/googleapis/api v0.0.0-20260526163538-3dc84a4a5aaa // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20260526163538-3dc84a4a5aaa // indirect
 	google.golang.org/grpc v1.81.1 // indirect
 	google.golang.org/protobuf v1.36.11 // indirect
 	gopkg.in/ini.v1 v1.67.2 // indirect
+	gopkg.in/yaml.v2 v2.4.0 // indirect
 )