Add full Docker image defaults, fix actor deadlocks, and improve dev experience

- Add Dockerfile.full and --all flag to install-agent CLI for pre-built images
- Centralize Docker image constant (FULL_IMAGE) pinned to 0.3.1-full
- Remove examples/shared/Dockerfile{,.dev} and daytona snapshot example
- Expand Docker docs with full runnable Dockerfile
- Fix self-deadlock in createWorkbenchSession (fire-and-forget provisioning)
- Audit and convert 12 task actions from wait:true to wait:false
- Add bun --hot for dev backend hot reload
- Remove --force from pnpm install in dev Dockerfile for faster startup
- Add env_file support to compose.dev.yaml for automatic credential loading
- Add mock frontend compose config and dev panel
- Update CLAUDE.md with wait:true policy and dev environment setup

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docs/quickstart.mdx

@@ -61,9 +61,11 @@ icon: "rocket"
 
       <Tab title="Docker">
         ```bash
-        docker run -e ANTHROPIC_API_KEY="sk-ant-..." \
+        docker run -p 2468:2468 \
+          -e ANTHROPIC_API_KEY="sk-ant-..." \
           -e OPENAI_API_KEY="sk-..." \
-          your-image
+          rivetdev/sandbox-agent:0.3.1-full \
+          server --no-token --host 0.0.0.0 --port 2468
         ```
       </Tab>
     </Tabs>
@@ -215,10 +217,7 @@ icon: "rocket"
     To preinstall agents:
 
     ```bash
-    sandbox-agent install-agent claude
-    sandbox-agent install-agent codex
-    sandbox-agent install-agent opencode
-    sandbox-agent install-agent amp
+    sandbox-agent install-agent --all
     ```
 
     If agents are not installed up front, they are lazily installed when creating a session.