chore: remove dead code — 8 components, 5 libs, 4 API routes, 4 npm packages, 30+ scripts, dead CSS, dead exports

Removed unused components:
- brainstorm-canvas, brainstorm-create-dialog, invite-dialog, manual-idea-dialog
- note-inline-editor, profile-page-header, quota-paywall, label-management-dialog

Removed dead lib files:
- api-auth.ts, color-harmony-recommendation.ts, label-storage.ts, modern-color-options.ts
- hooks/use-card-size-mode.ts

Removed dead API routes:
- ai/test-chat, ai/test-embeddings, ai/test-tags, admin/randomize-labels

Removed unused npm packages:
- cmdk, novel, tippy.js, react-force-graph-2d

Cleaned dead CSS from globals.css:
- acrylic-*, win11-shadow-*, muuri-grid/item, ai-glass, ai-tab-indicator, ai-send-btn, sidebar-view-toggle, memento-sidebar-depth

Removed 29 orphan scripts and 3 root orphan files

Cleaned dead exports from 8 lib files:
- NOTE_TYPE_CONFIG, getPublishableKey, PROVIDER_DEFAULTS, useNotes/useNote/invalidateNote, etc.

memento-note/app/api/ai/test-chat/route.ts

@@ -1,55 +0,0 @@
-import { NextRequest, NextResponse } from 'next/server'
-import { getChatProvider } from '@/lib/ai/factory'
-import { getSystemConfig } from '@/lib/config'
-import { auth } from '@/auth'
-
-export async function POST(request: NextRequest) {
-  const session = await auth()
-  if (!session?.user?.id) {
-    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
-  }
-  if ((session.user as any).role !== 'ADMIN') {
-    return NextResponse.json({ error: 'Forbidden' }, { status: 403 })
-  }
-
-  try {
-    const config = await getSystemConfig()
-    const provider = getChatProvider(config)
-
-    const testMessage = 'Réponds en exactement 3 mots : quel est ton nom ?'
-
-    const startTime = Date.now()
-    const response = await provider.generateText(testMessage)
-    const endTime = Date.now()
-
-    if (!response || response.trim().length === 0) {
-      return NextResponse.json(
-        {
-          success: false,
-          error: 'No response from chat provider',
-          model: config.AI_MODEL_CHAT || 'granite4:latest',
-        },
-        { status: 500 }
-      )
-    }
-
-    return NextResponse.json({
-      success: true,
-      model: config.AI_MODEL_CHAT || 'granite4:latest',
-      chatResponse: response.trim(),
-      responseTime: endTime - startTime,
-    })
-  } catch (error: any) {
-    const config = await getSystemConfig()
-
-    return NextResponse.json(
-      {
-        success: false,
-        error: error.message || 'Unknown error',
-        model: config.AI_MODEL_CHAT || 'granite4:latest',
-        stack: process.env.NODE_ENV === 'development' ? error.stack : undefined,
-      },
-      { status: 500 }
-    )
-  }
-}