fix: update proxy template with postgres 18 and init (#382)

* fix: suppress act() warnings and unhandled rejections in tests

Configure testing-library for React 18+ and suppress harmless act()
warnings that occur due to async state updates completing after test cleanup.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* feat: upgrade postgresql from 16 to 18

Upgrade devcontainer database to PostgreSQL 18.1 (released Sept 2025).

Key benefits:
- 3x performance with new Async I/O subsystem
- UUIDv7 function for timestamp-ordered UUIDs
- Virtual generated columns
- Skip scan on multicolumn B-tree indexes
- OAuth 2.0 authentication support

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* fix: add init to devcontainer to prevent zombie processes

Adds `init: true` to the devcontainer service which uses tini as PID 1.
This properly reaps zombie processes that accumulate from DevPod sessions.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* docs: add container naming convention for devpod

Adds instructions for configuring username-based container names
when multiple developers share the same remote server.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* fix: update proxy template with postgres 18 and init

- Upgrade PostgreSQL from 16 to 18
- Add init: true to prevent zombie processes

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

---------

Co-authored-by: Mohsin Hashmi <mhashmi@wiser.com>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: 3 people

.devcontainer/proxy/docker-compose.user.yml

@@ -23,6 +23,7 @@ services:
   devcontainer:
     image: ghcr.io/simpleaccounts/simpleaccounts-uae-devcontainer:latest
     container_name: dev-${USER_NAME:-alice}
+    init: true # Use tini as PID 1 to properly reap zombie processes
 
     volumes:
       - ../../:/workspaces/SimpleAccounts-UAE:cached
@@ -62,7 +63,7 @@ services:
       - 'traefik.http.services.${USER_NAME:-alice}-api.loadbalancer.server.port=8080'
 
   db:
-    image: postgres:16-alpine
+    image: postgres:18-alpine
     container_name: db-${USER_NAME:-alice}
     restart: unless-stopped
     volumes:

.devcontainer/proxy/setup-user.sh

@@ -123,6 +123,7 @@ services:
   devcontainer:
     image: ghcr.io/simpleaccounts/simpleaccounts-uae-devcontainer:latest
     container_name: dev-$USERNAME
+    init: true  # Use tini as PID 1 to properly reap zombie processes
 
     volumes:
       - ../../:/workspaces/SimpleAccounts-UAE:cached
@@ -186,7 +187,7 @@ services:
       - "traefik.http.services.$USERNAME-api.loadbalancer.server.port=8080"
 
   db:
-    image: postgres:16-alpine
+    image: postgres:18-alpine
     container_name: db-$USERNAME
     restart: unless-stopped
     volumes: