WIP: Fix Electron build issues and migrate to @nostr/tools

- Fix TypeScript compilation errors in platform services
- Add missing rotateCamera method and isNativeApp property
- Fix index.html path resolution for packaged Electron apps
- Create separate Vite config for Electron renderer process
- Migrate from nostr-tools to @nostr/tools via JSR for ESM compatibility
- Update all Vite configs to handle mixed npm/JSR package management
- Add comprehensive documentation in BUILDING.md
- Fix preload script path resolution in packaged builds

Resolves build failures with deep imports and missing UI in AppImage.

src/interfaces/common.ts

@@ -4,7 +4,7 @@ export interface GenericVerifiableCredential {
   "@type": string;
   name?: string;
   description?: string;
-  agent?: string;
+  agent?: string | { identifier: string };
   [key: string]: unknown;
 }