chore(deploy): use Neon Postgres instead of Render's managed database (#377)

render.yaml

@@ -1,25 +1,42 @@
 # Render Blueprint (#340) for a single-service PARTHA deployment: one web
 # service (FastAPI serving both the API and the built frontend, per #339),
-# one PostgreSQL database, one persistent disk for cloned/uploaded
-# repositories. Docker-based rather than Render's native Python runtime,
-# because the build needs Node to build the frontend before the Python
-# service ever starts -- see ./Dockerfile.
+# one persistent disk for cloned/uploaded repositories, and PostgreSQL
+# brought in from an external provider (Neon) rather than Render's own
+# managed database -- Render's free Postgres expires after 90 days; Neon's
+# free tier does not. Docker-based rather than Render's native Python
+# runtime, because the build needs Node to build the frontend before the
+# Python service ever starts -- see ./Dockerfile.
 #
 # Before deploying from this blueprint:
-#   1. Choose a plan for both the web service and the database in Render's
-#      dashboard when you create them -- this file intentionally doesn't
-#      pin one, since pricing/plan names change and that's a cost decision,
-#      not an engineering one. The web service's plan must support a
-#      persistent disk (the free tier does not).
-#   2. After the service exists, set AI_ENCRYPTION_KEY manually in the
-#      Render dashboard (Environment tab) -- generate it with:
+#   1. Choose a plan for the web service in Render's dashboard when you
+#      create it -- this file intentionally doesn't pin one, since
+#      pricing/plan names change and that's a cost decision, not an
+#      engineering one. IMPORTANT: this service has a persistent disk
+#      (below), and Render's free web-service tier does not support
+#      persistent disks at all (confirmed directly against Render's own
+#      docs) -- a free-tier deploy of this blueprint as-is will not get to
+#      keep the disk. That's a real product decision (accept a paid tier to
+#      keep durable repository storage, or accept ephemeral/ non-persistent
+#      storage on the free tier), not something to resolve by editing this
+#      comment -- see the PR/issue discussion for the current status.
+#   2. Create a project in Neon (or your Postgres provider of choice) and
+#      set DATABASE_URL manually in the Render dashboard (Environment tab)
+#      to its connection string. It is marked `sync: false` below for the
+#      same reason AI_ENCRYPTION_KEY is: there is nothing here for Render
+#      to generate or provision -- the value comes from outside Render
+#      entirely. app.core.config normalizes a bare postgres:// or
+#      postgresql:// scheme (what Neon and most managed providers hand
+#      back) to postgresql+psycopg:// itself, so Neon's connection string
+#      can be pasted in as-is, query parameters (e.g. ?sslmode=require)
+#      included.
+#   3. Set AI_ENCRYPTION_KEY manually in the same tab -- generate it with:
 #        python -c "from cryptography.fernet import Fernet; print(Fernet.generate_key().decode())"
 #      It is marked `sync: false` below on purpose: Render's generic
 #      generateValue only produces a random string, not the specific
 #      URL-safe-base64-of-32-bytes shape a Fernet key requires.
-#   3. AUTH_SECRET_KEY is auto-generated by Render (`generateValue: true`)
+#   4. AUTH_SECRET_KEY is auto-generated by Render (`generateValue: true`)
 #      and needs no manual step.
-#   4. Update CORS_ORIGINS below if the public domain changes from
+#   5. Update CORS_ORIGINS below if the public domain changes from
 #      www.partha.uk.
 #
 # Database migrations run as part of the container's own startup command
@@ -40,9 +57,7 @@ services:
       - key: LOG_FORMAT
         value: json
       - key: DATABASE_URL
-        fromDatabase:
-          name: partha-db
-          property: connectionString
+        sync: false
       - key: STORAGE_PATH
         value: /var/data/storage
       - key: CORS_ORIGINS
@@ -55,7 +70,3 @@ services:
       name: partha-storage
       mountPath: /var/data
       sizeGB: 5
-
-databases:
-  - name: partha-db
-    postgresMajorVersion: "16"