chore(compose): add shared json-file logging config and component labels

Introduce x-logging anchor with json-file driver, size/file caps, and
container name tagging so Alloy on puck can reliably tail every service
through the Docker socket. Apply to all services and inject
MNEMOSYNE_COMPONENT env vars (init/app/mcp/worker) for consistent log
attribution both

docker-compose.yaml

@@ -47,6 +47,20 @@
 # and is the typical re-run target after embedding-model changes).
 # =============================================================================
 
+# -----------------------------------------------------------------------------
+# Shared logging config — JSON to stdout, picked up by Alloy via the Docker
+# socket on the host and shipped to Loki. Pinning json-file (Docker's default)
+# so Alloy's discovery.docker + loki.source.docker on puck sees a consistent
+# driver across every service, and bounding log retention per container so a
+# misbehaving service can't fill the disk between Alloy tails.
+# -----------------------------------------------------------------------------
+x-logging: &default-logging
+  driver: json-file
+  options:
+    tag: "{{.Name}}"
+    max-size: "10m"
+    max-file: "5"
+
 
 services:
   # ── Static-file seeder: copies /app/staticfiles into the shared volume on
@@ -60,6 +74,7 @@ services:
     volumes:
       - mnemosyne-static:/shared-static
     restart: "no"
+    logging: *default-logging
 
   # ── Init sidecar: one-shot Postgres migrate + library-type seed. Runs on
   # every `up` and exits. Long-running services below depend on
@@ -92,10 +107,16 @@ services:
       - DB_PORT=${DB_PORT}
       # Neo4j (load_library_types writes Library defaults into the graph)
       - NEOMODEL_NEO4J_BOLT_URL=${NEOMODEL_NEO4J_BOLT_URL}
-      # Logging
+      # Logging (MNEMOSYNE_COMPONENT is injected by settings.py into every
+      # log line as a static JSON field; Alloy on puck reads the compose
+      # service name directly off the Docker label and uses that as the
+      # Loki `component` label, but we still set it here so operators
+      # tail-ing ``docker logs`` see the same attribution)
+      - MNEMOSYNE_COMPONENT=init
       - LOGGING_LEVEL=${LOGGING_LEVEL}
       - DJANGO_LOGGING_LEVEL=${DJANGO_LOGGING_LEVEL}
     restart: "no"
+    logging: *default-logging
 
 
   # ── App: Django REST API + admin ──────────────────────────────────────────
@@ -154,9 +175,11 @@ services:
       - RERANKER_MAX_CANDIDATES=${RERANKER_MAX_CANDIDATES}
       - RERANKER_TIMEOUT=${RERANKER_TIMEOUT}
       # Logging
+      - MNEMOSYNE_COMPONENT=app
       - LOGGING_LEVEL=${LOGGING_LEVEL}
       - DJANGO_LOGGING_LEVEL=${DJANGO_LOGGING_LEVEL}
     restart: unless-stopped
+    logging: *default-logging
     depends_on:
       static-init:
         condition: service_completed_successfully
@@ -228,9 +251,11 @@ services:
       - RERANKER_MAX_CANDIDATES=${RERANKER_MAX_CANDIDATES}
       - RERANKER_TIMEOUT=${RERANKER_TIMEOUT}
       # Logging
+      - MNEMOSYNE_COMPONENT=mcp
       - LOGGING_LEVEL=${LOGGING_LEVEL}
       - DJANGO_LOGGING_LEVEL=${DJANGO_LOGGING_LEVEL}
     restart: unless-stopped
+    logging: *default-logging
     depends_on:
       init:
         condition: service_completed_successfully
@@ -303,9 +328,11 @@ services:
       - EMBEDDING_BATCH_SIZE=${EMBEDDING_BATCH_SIZE}
       - EMBEDDING_TIMEOUT=${EMBEDDING_TIMEOUT}
       # Logging
+      - MNEMOSYNE_COMPONENT=worker
       - LOGGING_LEVEL=${LOGGING_LEVEL}
       - CELERY_LOGGING_LEVEL=${CELERY_LOGGING_LEVEL}
     restart: unless-stopped
+    logging: *default-logging
     depends_on:
       app:
         condition: service_healthy
@@ -324,6 +351,7 @@ services:
   web:
     image: nginx:alpine
     restart: unless-stopped
+    logging: *default-logging
     depends_on:
       app:
         condition: service_healthy