feat(kon): scaffold hybrid modular workspace

- Cargo workspace with 6 domain crates: core, audio, transcription, ai-formatting, storage, cloud-providers
- Minimal Tauri shell (lib.rs + main.rs) with plugin registration
- Svelte 5 frontend copied from Ramble v0.2
- All crates compile as empty stubs
- App identifier: uk.co.corbel.kon

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src-tauri/gen/schemas/capabilities.json

@@ -0,0 +1 @@
+{"default":{"identifier":"default","description":"Capability for the main window","local":true,"windows":["main","tasks-float"],"permissions":["core:default","core:window:allow-start-dragging","core:window:allow-set-always-on-top","core:window:allow-minimize","core:window:allow-toggle-maximize","core:window:allow-is-maximized","core:window:allow-close","core:window:allow-hide","core:window:allow-show","core:window:allow-set-focus","opener:default","dialog:default","global-shortcut:allow-register","global-shortcut:allow-unregister"]}}