docs: update all MCP documentation for 22 tools + API key auth

- Rewrite mcp-server/README.md: clean structure, auth section, 22 tools
- Rewrite N8N-CONFIG.md: remove hardcoded IPs, add x-api-key auth flow
- Rewrite N8N-WORKFLOWS.md: simplified, removed AI proxy tool references
- Update README.md/README.fr.md: 37→22 tools, add auth mention
- Update GUIDE.md/GUIDE.en.md: remove AI/API key tool tables, add auth
- Update DEPLOY.md: SSE → Streamable HTTP in architecture diagram

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

README.md

@@ -26,7 +26,7 @@ A smart, AI-powered note-taking app. Like Google Keep, but with notebooks, seman
 - Visual workflow builder
 
 **Integrations**
-- MCP Server with **37 tools** - connect Claude Desktop, N8N, or any MCP client
+- MCP Server with **22 tools** - connect Claude Desktop, N8N, or any MCP client
 - REST API for custom integrations
 - RSS feed support
 - Canvas/Lab whiteboard (Excalidraw)
@@ -115,9 +115,9 @@ Connect AI agents to your notes via the Model Context Protocol.
 }
 ```
 
-**37 tools available** - notes CRUD, notebooks, labels, AI operations (tag generation, title suggestions, memory echo, batch organize), reminders, and API key management.
+**22 tools available** - notes CRUD, notebooks, labels, reminders, search, export/import. Each API key is scoped to a user so only their notes are accessible.
 
-For N8N or HTTP clients, use Streamable HTTP mode: `http://localhost:3001/mcp`
+For N8N or HTTP clients, use Streamable HTTP mode: `http://localhost:3001/mcp` with `x-api-key` header auth.
 
 ---
 
@@ -154,10 +154,11 @@ Momento/
 │   ├── prisma/               # Schema + migrations
 │   ├── locales/              # 15 i18n JSON files
 │   └── Dockerfile            # Multi-stage build
-├── mcp-server/               # MCP server (37 tools)
+├── mcp-server/               # MCP server (22 tools)
 │   ├── index.js              # stdio mode
 │   ├── index-sse.js          # HTTP Streamable mode
 │   ├── tools.js              # Tool definitions
+│   ├── auth.js               # API key authentication
 │   └── Dockerfile            # Container build
 └── n8n-memento-workflow.json # Pre-configured N8N workflow
 ```