docs: update all documentation for OpenCode and deployment

- Update architecture.md with spawn service and auth proxy sections
- Update deployment.md with production stack details
- Update development.md with spawn workflow documentation
- Update mvp-scope.md, project-brief.md, tool-manifest-spec.md
- Update conversation-handoff.md with current status
- Replace all RunFusion references with OpenCode

docs/tool-manifest-spec.md

@@ -5,7 +5,7 @@
 
 ## Overview
 
-Headquarter is a manifest-driven platform: every containerized tool (RunFusion, code-server, and future tools) is declared by a YAML manifest. The orchestration backend reads these manifests to generate Docker Compose services, Traefik routing labels, volume mounts, and resource constraints.
+Headquarter is a manifest-driven platform: every containerized tool (OpenCode, code-server, and future tools) is declared by a YAML manifest. The orchestration backend reads these manifests to generate Docker Compose services, Traefik routing labels, volume mounts, and resource constraints.
 
 **Design goal:** Adding a new standard container tool requires only a YAML manifest—no backend code changes.
 
@@ -135,17 +135,17 @@ traefik:
 7. `memory_mb`, if set, must be ≥ 16.
 8. If `traefik.enabled` is `true`, at least one port must have `primary: true`.
 
-## Example: RunFusion Manifest
+## Example: OpenCode Manifest
 
 ```yaml
-id: runfusion
-name: RunFusion
-description: Executable Node.js environment for running and developing applications.
+id: opencode
+name: OpenCode
+description: AI-powered terminal-based development environment with web interface.
 version: "1.0.0"
-image: node:22-slim
+image: ghcr.io/opencode-ai/opencode:latest
 runtime_working_dir: /workspace
 ports:
-  - container_port: 8080
+  - container_port: 3000
     protocol: tcp
     name: http
     primary: true
@@ -156,32 +156,28 @@ workspace_mounts:
     read_only: false
 config_mounts:
   - type: volume
-    source_pattern: "{user_config}/runfusion"
-    target: /home/node/.config
+    source_pattern: "{user_config}/opencode"
+    target: /root/.config/opencode
     read_only: false
 env:
-  NODE_ENV: development
+  TERM: xterm-256color
+  FORCE_COLOR: "1"
 health_check:
   type: http
   path: /
-  port: 8080
+  port: 3000
   interval_seconds: 10
   timeout_seconds: 5
   retries: 3
-  start_period_seconds: 10
+  start_period_seconds: 15
 resource_limits:
   cpus: 2.0
-  memory_mb: 2048
+  memory_mb: 4096
   memory_swap_mb: -1
-executable:
-  node_version: "22"
-  package_manager: npm
-  bootstrap_commands: []
-  install_commands: []
 traefik:
   enabled: true
-  subdomain_prefix: runfusion
-  port: 8080
+  subdomain_prefix: opencode
+  port: 3000
   middlewares: []
   strip_prefix: false
 ```