feat(app): content detection overhaul, apps tab, chat UX, web search

- Overhaul content detection: expand all query/response classifiers with
  broader AI response patterns (news, music, books, TV, places, websites)
- Add Nostr detection (isNostrQuery, isNostrLikeResponse) and App detection
  (isAppQuery, isAppLikeResponse) classifiers
- Add bare domain extraction from AI text (e.g. "check out damus.io")
- Add Apps tab with curated database of ~30 Nostr + Bitcoin ecosystem apps
  (clients, wallets, privacy tools, node software, dev tools)
- Create AppsGrid + AppDetail components with search, filtering, how-to
- Wire app extraction and Nostr detection into useContentPanel
- Add PromptIndex badges for Apps and Nostr tabs
- Chat UX: dedicated history button, settings modal (memory + advanced),
  fix collapsed chat v-if/v-else chain bug
- Web search: add Brave Search API as primary backend, expand SearXNG pool
- iOS HIG: comprehensive mobile UX rules in cursor rules + CLAUDE.md

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

packages/core/src/index.test.ts

@@ -0,0 +1,83 @@
+import { describe, it, expect } from 'vitest'
+import {
+  registerPlugin,
+  unregisterPlugin,
+  getPlugin,
+  getPluginsByType,
+  registerRenderer,
+  getRendererForContentType,
+  getAllRenderers,
+} from './plugins/registry'
+import type { AIUIPlugin } from './types/plugin'
+import type { RendererDefinition } from './types/renderer'
+
+function createMockPlugin(overrides: Partial<AIUIPlugin> = {}): AIUIPlugin {
+  return {
+    id: 'test-plugin',
+    name: 'Test Plugin',
+    version: '1.0.0',
+    type: 'ai-provider',
+    async init() {},
+    async destroy() {},
+    async isAvailable() { return true },
+    ...overrides,
+  }
+}
+
+describe('core exports', () => {
+  it('exports plugin registry functions', () => {
+    expect(registerPlugin).toBeTypeOf('function')
+    expect(unregisterPlugin).toBeTypeOf('function')
+    expect(getPlugin).toBeTypeOf('function')
+    expect(getPluginsByType).toBeTypeOf('function')
+  })
+
+  it('exports renderer registry functions', () => {
+    expect(registerRenderer).toBeTypeOf('function')
+    expect(getRendererForContentType).toBeTypeOf('function')
+    expect(getAllRenderers).toBeTypeOf('function')
+  })
+})
+
+describe('plugin registry', () => {
+  it('registers and retrieves a plugin', () => {
+    const plugin = createMockPlugin({ id: 'reg-test' })
+    registerPlugin(plugin)
+
+    const retrieved = getPlugin('reg-test')
+    expect(retrieved).toBeDefined()
+    expect(retrieved?.id).toBe('reg-test')
+
+    unregisterPlugin('reg-test')
+  })
+
+  it('unregisters a plugin', () => {
+    const plugin = createMockPlugin({ id: 'unreg-test' })
+    registerPlugin(plugin)
+    unregisterPlugin('unreg-test')
+
+    expect(getPlugin('unreg-test')).toBeUndefined()
+  })
+
+  it('filters plugins by type', () => {
+    const p1 = createMockPlugin({ id: 'type-a', type: 'ai-provider' })
+    const p2 = createMockPlugin({ id: 'type-b', type: 'storage' })
+    registerPlugin(p1)
+    registerPlugin(p2)
+
+    const providers = getPluginsByType('ai-provider')
+    expect(providers.some(p => p.id === 'type-a')).toBe(true)
+    expect(providers.some(p => p.id === 'type-b')).toBe(false)
+
+    unregisterPlugin('type-a')
+    unregisterPlugin('type-b')
+  })
+
+  it('skips duplicate registration', () => {
+    const plugin = createMockPlugin({ id: 'dup-test' })
+    registerPlugin(plugin)
+    registerPlugin(plugin) // should warn but not throw
+
+    unregisterPlugin('dup-test')
+  })
+})