refactor: move slow performance tests to extra test suite

.drone.yml

@@ -83,8 +83,8 @@ steps:
       - mix local.hex --force
       # Fetch dependencies
       - mix deps.get
-      # Run tests
-      - mix test
+      # Run fast tests (excludes slow/performance tests)
+      - mix test --exclude slow
 
   - name: rebuild-cache
     image: drillster/drone-volume-cache
@@ -178,3 +178,52 @@ steps:
       - unset GIT_COMMITTER_NAME GIT_COMMITTER_EMAIL GIT_AUTHOR_NAME GIT_AUTHOR_EMAIL
       - renovate-config-validator
       - renovate
+
+---
+kind: pipeline
+type: docker
+name: nightly-tests
+
+trigger:
+  event:
+    - cron
+  cron:
+    - "0 2 * * *"  # Run at 2 AM daily
+
+services:
+  - name: postgres
+    image: docker.io/library/postgres:18.1
+    environment:
+      POSTGRES_USER: postgres
+      POSTGRES_PASSWORD: postgres
+
+steps:
+  - name: wait_for_postgres
+    image: docker.io/library/postgres:18.1
+    commands:
+      # Wait for postgres to become available
+      - |
+        for i in {1..20}; do
+          if pg_isready -h postgres -U postgres; then
+            exit 0
+          else
+            true
+          fi
+          sleep 2
+        done
+        echo "Postgres did not become available, aborting."
+        exit 1
+
+  - name: test-slow
+    image: docker.io/library/elixir:1.18.3-otp-27
+    environment:
+      MIX_ENV: test
+      TEST_POSTGRES_HOST: postgres
+      TEST_POSTGRES_PORT: 5432
+    commands:
+      # Install hex package manager
+      - mix local.hex --force
+      # Fetch dependencies
+      - mix deps.get
+      # Run only all tests
+      - mix test