feat: add native runtime customization

OpenCode and Continue customization was previously planned but unavailable, and Runtime-native capabilities were not represented consistently across providers. GoodBuddy now provides secure Main-owned customization settings, truthful native inventories, OpenCode Agents and Commands, Continue Rules and Prompts, DSH Web Search/Fetch, MCP Prompt and Resource metadata, and manual compaction where supported.

Native capabilities are presented in eleven accessible tabs with Tools separated from Commands, LSP, and Formatters. Tool source and Ask/Execute availability are explicit, external OpenCode remains connection-only, Continue reports unsupported static tool discovery instead of advertising unreachable Skills, and disposable inventory probes avoid retaining background runtimes.

Ask remains read-only at the Runtime boundary, Execute keeps the existing authorization controls, and credentials remain confined to Main.

Release note: 新增 OpenCode、Continue 与 DeepSeek Harness 的 Runtime 原生定制与真实能力清单；工具来源、Ask/Execute 可用性、上下文压缩和 MCP 元数据现在可清晰查看，同时继续保持 Main 进程凭据保护与现有权限边界。

src/main/agent/create-runtime.test.ts

@@ -1,6 +1,7 @@
 import { describe, expect, it, vi } from 'vitest'
 import type { ResolvedRuntimeSettings } from '../runtime-settings-store'
 import type { BrowserToolService } from '../browser/browser-model-tools'
+import { defaultRuntimeCustomizationSettings } from '../../shared/contracts'
 import {
   createAgentRuntime,
   createModelProfileRuntime
@@ -63,6 +64,7 @@ function settings(
     knowledgeRerankEnabled: false,
     knowledgeRerankEndpoint: 'https://api.cohere.com/v1/rerank',
     knowledgeRerankModel: 'rerank-v3.5',
+    runtimeCustomization: defaultRuntimeCustomizationSettings,
     workspacePath: process.cwd(),
     toolApproval: 'always',
     ...overrides