fix: remove redundant confirmation for configuration changes

Configuration apply previously required a separate native confirmation even in Agent Runtime Execute mode, and failed in clients without an approval callback. Use existing work-mode and tool authorization instead, preserving Ask read-only access and request-scoped plan validation. Update regression tests, tool descriptions and documentation.

Validation: 267 focused tests passed; typecheck and changed-file lint passed. Full tests timed out with failures in other modules; repository lint reported errors in unchanged files.

Release note: Execute 模式下通过 Agent Runtime 修改 GoodBuddy 配置不再额外弹出确认框，Ask 模式仍保持只读。

src/main/agent/model-tool-provider.test.ts

@@ -1005,7 +1005,8 @@ describe('ModelToolProvider', () => {
       )
     ).toMatchObject({
       scopeKey: 'model:goodbuddy-config:apply',
-      allowPermanent: false
+      allowPermanent: false,
+      description: '该操作会按计划修改 GoodBuddy 应用偏好或扩展能力。'
     })
   })