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/lib/ai/services/index.ts

@@ -0,0 +1,70 @@
+/**
+ * AI Services Index
+ * Central exports for all AI-powered services
+ */
+
+// Language Detection
+export { LanguageDetectionService } from './language-detection.service'
+
+// Title Suggestions
+export {
+  TitleSuggestionService,
+  titleSuggestionService,
+  type TitleSuggestion
+} from './title-suggestion.service'
+
+// Embeddings
+export {
+  EmbeddingService,
+  embeddingService,
+  type EmbeddingResult
+} from './embedding.service'
+
+// Semantic Search
+export {
+  SemanticSearchService,
+  semanticSearchService,
+  type SearchResult,
+  type SearchOptions
+} from './semantic-search.service'
+
+// Paragraph Refactor
+export {
+  ParagraphRefactorService,
+  paragraphRefactorService,
+  type RefactorMode,
+  type RefactorOption,
+  type RefactorResult,
+  REFACTOR_OPTIONS
+} from './paragraph-refactor.service'
+
+// Memory Echo
+export {
+  MemoryEchoService,
+  memoryEchoService,
+  type MemoryEchoInsight
+} from './memory-echo.service'
+
+// Batch Organization
+export {
+  BatchOrganizationService,
+  batchOrganizationService,
+  type NoteForOrganization,
+  type NotebookOrganization,
+  type OrganizationPlan
+} from './batch-organization.service'
+
+// Auto Label Creation
+export {
+  AutoLabelCreationService,
+  autoLabelCreationService,
+  type SuggestedLabel,
+  type AutoLabelSuggestion
+} from './auto-label-creation.service'
+
+// Notebook Summary
+export {
+  NotebookSummaryService,
+  notebookSummaryService,
+  type NotebookSummary
+} from './notebook-summary.service'