Add assignment engine, FCM, WebSockets, city gate, and internal APIs

- internal/assignment: GEORADIUS miler assignment with retry/escalation,
  customer-side provider scoring, FCM notifications on assign
- internal/notify: Firebase Admin SDK (FCM) client initialisation
- internal/ws: WebSocket handlers for live parcel tracking and
  customer↔miler chat
- middlewares: city gate (pincode prefix validation), internal API key
  auth, WebSocket JWT auth
- controllers: InternalNotify + InternalReassign for machine-to-machine
  calls; pricing helpers wired into CreateCustomerBooking and CreateCRMBooking
- routes: /internal/*, /ws/bookings/:id/track, /ws/bookings/:id/chat
- models/users, models/doormile_pricing: new fields for device tokens,
  assignment state, pricing bands
- seed_data.sql: initial pricing seed rows

.env and Firebase service-account JSON intentionally excluded.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

go.mod

@@ -1,6 +1,6 @@
 module doormile
 
-go 1.24.0
+go 1.25.0
 
 require (
 	github.com/gofiber/fiber/v2 v2.52.10
@@ -9,16 +9,45 @@ require (
 	github.com/lib/pq v1.12.3
 	github.com/redis/go-redis/v9 v9.16.0
 	go.uber.org/zap v1.27.1
-	golang.org/x/crypto v0.31.0
+	golang.org/x/crypto v0.51.0
 	gorm.io/driver/postgres v1.5.11
 	gorm.io/gorm v1.25.12
 )
 
 require (
+	cel.dev/expr v0.25.2 // indirect
+	cloud.google.com/go v0.123.0 // indirect
+	cloud.google.com/go/auth v0.20.0 // indirect
+	cloud.google.com/go/auth/oauth2adapt v0.2.8 // indirect
+	cloud.google.com/go/compute/metadata v0.9.0 // indirect
+	cloud.google.com/go/firestore v1.22.0 // indirect
+	cloud.google.com/go/iam v1.11.0 // indirect
+	cloud.google.com/go/longrunning v1.0.0 // indirect
+	cloud.google.com/go/monitoring v1.29.0 // indirect
+	cloud.google.com/go/storage v1.62.1 // indirect
+	firebase.google.com/go/v4 v4.20.0 // indirect
+	github.com/GoogleCloudPlatform/opentelemetry-operations-go/detectors/gcp v1.32.0 // indirect
+	github.com/GoogleCloudPlatform/opentelemetry-operations-go/exporter/metric v0.56.0 // indirect
+	github.com/GoogleCloudPlatform/opentelemetry-operations-go/internal/resourcemapping v0.56.0 // indirect
+	github.com/MicahParks/keyfunc v1.9.0 // indirect
 	github.com/andybalholm/brotli v1.1.0 // indirect
 	github.com/cespare/xxhash/v2 v2.3.0 // indirect
+	github.com/cncf/xds/go v0.0.0-20260202195803-dba9d589def2 // indirect
 	github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f // indirect
+	github.com/envoyproxy/go-control-plane/envoy v1.37.0 // indirect
+	github.com/envoyproxy/protoc-gen-validate v1.3.3 // indirect
+	github.com/fasthttp/websocket v1.5.3 // indirect
+	github.com/felixge/httpsnoop v1.0.4 // indirect
+	github.com/go-jose/go-jose/v4 v4.1.4 // indirect
+	github.com/go-logr/logr v1.4.3 // indirect
+	github.com/go-logr/stdr v1.2.2 // indirect
+	github.com/gofiber/websocket/v2 v2.2.1 // indirect
+	github.com/golang-jwt/jwt/v4 v4.5.2 // indirect
+	github.com/golang/protobuf v1.5.4 // indirect
+	github.com/google/s2a-go v0.1.9 // indirect
 	github.com/google/uuid v1.6.0 // indirect
+	github.com/googleapis/enterprise-certificate-proxy v0.3.15 // indirect
+	github.com/googleapis/gax-go/v2 v2.22.0 // indirect
 	github.com/jackc/pgpassfile v1.0.0 // indirect
 	github.com/jackc/pgservicefile v0.0.0-20221227161230-091c0ba34f0a // indirect
 	github.com/jackc/pgx/v5 v5.5.5 // indirect
@@ -32,12 +61,34 @@ require (
 	github.com/nats-io/nats.go v1.31.0 // indirect
 	github.com/nats-io/nkeys v0.4.5 // indirect
 	github.com/nats-io/nuid v1.0.1 // indirect
+	github.com/planetscale/vtprotobuf v0.6.1-0.20240319094008-0393e58bdf10 // indirect
 	github.com/rivo/uniseg v0.4.7 // indirect
+	github.com/savsgio/gotils v0.0.0-20230208104028-c358bd845dee // indirect
+	github.com/spiffe/go-spiffe/v2 v2.6.0 // indirect
 	github.com/valyala/bytebufferpool v1.0.0 // indirect
 	github.com/valyala/fasthttp v1.51.0 // indirect
 	github.com/valyala/tcplisten v1.0.0 // indirect
+	go.opentelemetry.io/auto/sdk v1.2.1 // indirect
+	go.opentelemetry.io/contrib/detectors/gcp v1.43.0 // indirect
+	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.68.0 // indirect
+	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.68.0 // indirect
+	go.opentelemetry.io/otel v1.43.0 // indirect
+	go.opentelemetry.io/otel/metric v1.43.0 // indirect
+	go.opentelemetry.io/otel/sdk v1.43.0 // indirect
+	go.opentelemetry.io/otel/sdk/metric v1.43.0 // indirect
+	go.opentelemetry.io/otel/trace v1.43.0 // indirect
 	go.uber.org/multierr v1.10.0 // indirect
-	golang.org/x/sync v0.10.0 // indirect
-	golang.org/x/sys v0.28.0 // indirect
-	golang.org/x/text v0.21.0 // indirect
+	golang.org/x/net v0.54.0 // indirect
+	golang.org/x/oauth2 v0.36.0 // indirect
+	golang.org/x/sync v0.20.0 // indirect
+	golang.org/x/sys v0.44.0 // indirect
+	golang.org/x/text v0.37.0 // indirect
+	golang.org/x/time v0.15.0 // indirect
+	google.golang.org/api v0.279.0 // indirect
+	google.golang.org/appengine/v2 v2.0.6 // indirect
+	google.golang.org/genproto v0.0.0-20260511170946-3700d4141b60 // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20260511170946-3700d4141b60 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20260511170946-3700d4141b60 // indirect
+	google.golang.org/grpc v1.81.1 // indirect
+	google.golang.org/protobuf v1.36.11 // indirect
 )