fix(vision): build fallisce senza VISION_ENGINE_VERSION, healthcheck vero

Un build senza la variabile produceva un'immagine che partiva e
rispondeva "healthy" pur fallendo ogni richiesta, /health incluso: non
c'era un healthcheck a dirlo. Tre correzioni: RUN test -n
"$VISION_ENGINE_VERSION" in Dockerfile.vision dopo l'ARG, fallisce
subito con il comando da lanciare; healthcheck su /health nel servizio
vision di entrambi i compose; VISION_ENGINE_VERSION documentata in
.env.example accanto a VISION_WORKER_URL, che già c'era.

Verificato con docker build reale: senza la variabile fallisce al passo
del test con il messaggio atteso; con la variabile impostata l'immagine
si costruisce, il container parte, e python3 -c
"urllib.request.urlopen('http://localhost:8100/health')" - lo stesso
comando usato nell'healthcheck - risponde 200 con l'engine_version
giusta.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_014BBnuACZSCJqXrMYC3LUMU

.env.example

@@ -33,6 +33,11 @@ STATION_SWITCH_ENABLED=0
 # --- Vision ---
 # Internal address of the vision worker. Never exposed outside tmflow-net.
 VISION_WORKER_URL=http://vision:8100
+# The pinned VisionSuite commit, stamped into the vision image at build time
+# (Dockerfile.vision ARG). Required: `docker compose build vision` fails
+# immediately without it. Set with:
+#   VISION_ENGINE_VERSION=$(git -C vendor/visionsuite rev-parse HEAD)
+VISION_ENGINE_VERSION=
 
 # --- File Storage ---
 # Resolved against the project root in src/backend/config.py.

Dockerfile.vision

@@ -24,6 +24,14 @@ COPY src/vision_worker/ ./src/vision_worker/
 #   VISION_ENGINE_VERSION=$(git -C vendor/visionsuite rev-parse HEAD) \
 #     docker compose build vision
 ARG VISION_ENGINE_VERSION
+# I4: a build without the commit must fail now, at build time - not later, at
+# every request including /health, with a container Docker still reports as
+# healthy because no healthcheck existed to say otherwise.
+RUN test -n "$VISION_ENGINE_VERSION" || { \
+        echo "VISION_ENGINE_VERSION is required. Build with:"; \
+        echo '  VISION_ENGINE_VERSION=$(git -C vendor/visionsuite rev-parse HEAD) docker compose build vision'; \
+        exit 1; \
+    }
 ENV VISION_ENGINE_VERSION=${VISION_ENGINE_VERSION}
 
 EXPOSE 8100

docker-compose.dev.yml

@@ -50,6 +50,12 @@ services:
         VISION_ENGINE_VERSION: ${VISION_ENGINE_VERSION:-}
     container_name: tmflow-vision
     restart: unless-stopped
+    healthcheck:
+      test: ["CMD", "python3", "-c", "import urllib.request; urllib.request.urlopen('http://localhost:8100/health', timeout=5)"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+      start_period: 20s
     networks:
       - tmflow-net
 

docker-compose.yml

@@ -59,6 +59,12 @@ services:
         VISION_ENGINE_VERSION: ${VISION_ENGINE_VERSION:-}
     container_name: tmflow-vision
     restart: unless-stopped
+    healthcheck:
+      test: ["CMD", "python3", "-c", "import urllib.request; urllib.request.urlopen('http://localhost:8100/health', timeout=5)"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+      start_period: 20s
     networks:
       - tmflow-net