feat: add universal adapters for browser compatibility

- Create universal adapters for cross-platform support (browser/Node/serverless)
- Replace Node.js-specific imports with universal implementations
- Add OPFS support for browser persistent storage
- Maintain same BrainyData interface across all environments
- Enable real Brainy usage in browser console UI
- Keep package size optimized (no bloat)

Universal adapters in /src/universal/:
- uuid.ts: Cross-platform UUID generation
- crypto.ts: Browser/Node crypto operations
- fs.ts: OPFS/FileSystem/Memory storage adapter
- path.ts: Universal path operations
- events.ts: EventEmitter compatibility layer

This enables 'write once, run anywhere' for Brainy while maintaining
the exact same API. No breaking changes to existing code.

src/mcp/brainyMCPAdapter.ts

@@ -6,7 +6,7 @@
  * and getting relationships.
  */
 
-import { v4 as uuidv4 } from 'uuid'
+import { v4 as uuidv4 } from '../universal/uuid.js'
 import { BrainyDataInterface } from '../types/brainyDataInterface.js'
 import { 
   MCPRequest, 

src/mcp/brainyMCPService.ts

@@ -7,7 +7,7 @@
  * for external model access.
  */
 
-import { v4 as uuidv4 } from 'uuid'
+import { v4 as uuidv4 } from '../universal/uuid.js'
 import { BrainyDataInterface } from '../types/brainyDataInterface.js'
 import {
   MCPRequest,

src/mcp/mcpAugmentationToolset.ts

@@ -5,7 +5,7 @@
  * It provides methods for getting available tools and executing tools.
  */
 
-import { v4 as uuidv4 } from 'uuid'
+import { v4 as uuidv4 } from '../universal/uuid.js'
 import { 
   MCPResponse, 
   MCPToolExecutionRequest,