refactor: replace emulator with WireMock, add E2E encryption and rate-limit tests

- Replace custom phone emulator with WireMock for FCM and webhook stubs
- Refactor tests to use httpsms-go SDK instead of raw HTTP calls
- Add TestSendSMS_Encrypted: E2E encryption round-trip verification
- Add TestReceiveSMS_Encrypted: incoming encrypted message test
- Add TestSendSMS_RateLimit: verify >=6s gap between FCM pushes (10 msg/min)
- Add TestSendSMS_OutstandingFlow: verify outstanding message retrieval
- All tests assert webhook JWT (HMAC-SHA256, claims validation)
- Each test creates isolated phone with random number for parallel execution
- Update CI workflow: checkout httpsms-go SDK, increase test timeout to 300s
- Simplify seed.sql to only user data (phones created dynamically)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: AchoArnold

.github/workflows/integration-test.yml

@@ -18,11 +18,22 @@ jobs:
       - name: Checkout 🛎
         uses: actions/checkout@v4
 
+      - name: Checkout httpsms-go SDK
+        uses: actions/checkout@v4
+        with:
+          repository: NdoleStudio/httpsms-go
+          path: httpsms-go
+
       - name: Set up Go
         uses: actions/setup-go@v5
         with:
           go-version: "1.23"
 
+      - name: Fix SDK replace path for CI
+        working-directory: ./tests
+        run: |
+          sed -i 's|replace github.com/NdoleStudio/httpsms-go => ../../httpsms-go|replace github.com/NdoleStudio/httpsms-go => ../httpsms-go|' go.mod
+
       - name: Generate Firebase credentials
         run: |
           bash tests/generate-firebase-credentials.sh tests/firebase-credentials.json
@@ -59,7 +70,7 @@ jobs:
 
       - name: Run integration tests 🧪
         working-directory: ./tests
-        run: go test -v -timeout 120s ./...
+        run: go test -v -timeout 300s ./...
 
       - name: Collect logs on failure 📋
         if: failure()

tests/.env.test

@@ -7,7 +7,7 @@ EVENTS_QUEUE_NAME=events-local
 EVENTS_QUEUE_ENDPOINT=http://localhost:8000/v1/events
 EVENTS_QUEUE_USER_API_KEY=system-user-api-key
 EVENTS_QUEUE_USER_ID=system-user-id
-FCM_ENDPOINT=http://emulator:9090
+FCM_ENDPOINT=http://wiremock:8080
 DATABASE_URL=postgresql://dbusername:dbpassword@postgres:5432/httpsms
 DATABASE_URL_DEDICATED=postgresql://dbusername:dbpassword@postgres:5432/httpsms
 REDIS_URL=redis://@redis:6379

tests/docker-compose.yml

@@ -25,17 +25,14 @@ services:
       timeout: 5s
       retries: 10
 
-  emulator:
-    build:
-      context: ./emulator
+  wiremock:
+    image: wiremock/wiremock:3x
     ports:
-      - "9090:9090"
-    environment:
-      API_BASE_URL: http://api:8000
-      PHONE_API_KEY: pk_test-phone-api-key
-      PORT: "9090"
+      - "8080:8080"
+    volumes:
+      - ./wiremock/mappings:/home/wiremock/mappings:ro
     healthcheck:
-      test: ["CMD", "wget", "--spider", "-q", "http://localhost:9090/health"]
+      test: ["CMD", "curl", "-f", "http://localhost:8080/__admin/health"]
       interval: 5s
       timeout: 5s
       retries: 10
@@ -50,7 +47,7 @@ services:
         condition: service_healthy
       redis:
         condition: service_healthy
-      emulator:
+      wiremock:
         condition: service_healthy
     env_file:
       - .env.test