feat: rename keep-notes to memento-note, migrate to PostgreSQL, fix MCP bugs

- Rename directory keep-notes -> memento-note with all code references
- Prisma: SQLite -> PostgreSQL (both app and MCP server schemas)
- Sync MCP schema with main app (add missing fields, relations, indexes)
- Delete 17 SQLite migrations (clean slate for PostgreSQL)
- Remove SQLite dependencies (@libsql/client, better-sqlite3, etc.)
- Fix MCP server: hardcoded Windows DB paths -> DATABASE_URL env var
- Fix MCP server: .dockerignore excluded index-sse.js (SSE mode broken)
- MCP Dockerfile: node:20 -> node:22
- Docker Compose: add postgres service, remove SQLite volume
- Generate favicon.ico, icon-192.png, icon-512.png, apple-icon.png
- Update layout.tsx icons and manifest.json for PNG icons
- Update all .env files for PostgreSQL
- Rewrite README.md with updated sections
- Remove mcp-server/node_modules and prisma/client-generated from git tracking

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

memento-note/app/api/ai/config/route.ts

@@ -0,0 +1,26 @@
+import { NextRequest, NextResponse } from 'next/server'
+import { getSystemConfig } from '@/lib/config'
+
+export async function GET(request: NextRequest) {
+  try {
+    const config = await getSystemConfig()
+
+    return NextResponse.json({
+      AI_PROVIDER_TAGS: config.AI_PROVIDER_TAGS || 'not set',
+      AI_MODEL_TAGS: config.AI_MODEL_TAGS || 'not set',
+      AI_PROVIDER_EMBEDDING: config.AI_PROVIDER_EMBEDDING || 'not set',
+      AI_MODEL_EMBEDDING: config.AI_MODEL_EMBEDDING || 'not set',
+      OPENAI_API_KEY: config.OPENAI_API_KEY ? '***configured***' : '',
+      CUSTOM_OPENAI_API_KEY: config.CUSTOM_OPENAI_API_KEY ? '***configured***' : '',
+      CUSTOM_OPENAI_BASE_URL: config.CUSTOM_OPENAI_BASE_URL || '',
+      OLLAMA_BASE_URL: config.OLLAMA_BASE_URL || 'not set'
+    })
+  } catch (error: any) {
+    return NextResponse.json(
+      {
+        error: error.message || 'Failed to fetch config'
+      },
+      { status: 500 }
+    )
+  }
+}