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/cli.mdx

@@ -39,20 +39,24 @@ Notes:
 
 ## install-agent
 
-Install or reinstall a single agent.
+Install or reinstall a single agent, or every supported agent with `--all`.
 
 ```bash
-sandbox-agent install-agent <AGENT> [OPTIONS]
+sandbox-agent install-agent [<AGENT>] [OPTIONS]
 ```
 
 | Option | Description |
 |--------|-------------|
+| `--all` | Install every supported agent |
 | `-r, --reinstall` | Force reinstall |
-| `--agent-version <VERSION>` | Override agent package version |
-| `--agent-process-version <VERSION>` | Override agent process version |
+| `--agent-version <VERSION>` | Override agent package version (conflicts with `--all`) |
+| `--agent-process-version <VERSION>` | Override agent process version (conflicts with `--all`) |
+
+Examples:
 
 ```bash
 sandbox-agent install-agent claude --reinstall
+sandbox-agent install-agent --all
 ```
 
 ## opencode (experimental)