Add standalone executable packaging with esbuild + pkg

- Add npm scripts for building Windows/Linux/macOS executables
- Replace uuid package with crypto.randomUUID() for ESM compatibility
- Use esbuild to pre-bundle code before pkg (fixes MCP SDK subpath exports)
- Update CLI name from 'memory' to 'cortex'
- Update USAGE.md with build instructions and standalone setup
- Add bundle/ and build/ to .gitignore

src/core/store.ts

@@ -1,4 +1,4 @@
-import { v4 as uuid } from 'uuid';
+import { randomUUID as uuid } from 'crypto';
 import { getDb } from './db';
 import { Node, Edge, AddNodeInput, UpdateNodeInput, ListOptions, QueryOptions, SearchResult, EdgeType } from '../types';
 import { hybridSearch, deserializeEmbedding } from './search/index';