feat: add direct model programming agents

Direct model conversations can now execute bounded platform-native processes and delegate one level of programming work without duplicating tools in Agent Runtimes. Process and Subagent activity follows existing workspace, mode, approval, cancellation, and lifecycle boundaries, with chat attribution and complete feature documentation.

Remove the static Renderer bundle baseline gate and its build-only manifests; production builds continue to compile all processes and verify the control-plane installer. Also include the pending documentation link normalization.

Release note: 直连模型现在可在 Execute 模式运行本机命令，并可委派编程 Subagent 完成修改、测试和复核；构建流程不再因静态 Renderer 包体基线阻塞。

src/main/agent/opencode-subagent.test.ts

@@ -37,7 +37,10 @@ describe('OpenCode native subagent events', () => {
     })
     expect(completed).toMatchObject({
       childTaskId: running?.childTaskId,
-      expertId: running?.expertId,
+      expertId:
+        running && 'expertId' in running
+          ? running.expertId
+          : undefined,
       state: 'completed',
       output: 'Architecture review complete.'
     })