chore: rebrand from Kon/Corbie to Magnotia

Replace all instances of the legacy product names "Kon" and "Corbie" with
"Magnotia" across user-facing copy, code identifiers, package names, bundle
ids, file paths, and documentation. Preserves the unrelated "konsole" (KDE
terminal) reference and the parent CORBEL company name.

- Renames 10 Rust crates (kon-* → magnotia-*) and the tauri binary
- Updates package.json, tauri.conf.json (productName + identifier)
- Renames CSS classes (kon-rh-* → magnotia-rh-*) and animations
- Renames brand and roadmap docs
- Regenerates Cargo.lock and package-lock.json

Verified: svelte-check passes; pure-rust crates compile under new names.

HANDOVER-2026-04-18.md

@@ -1,11 +1,11 @@
 ---
 name: handover-2026-04-18
 type: reference
-tags: [handover, session, kon]
+tags: [handover, session, magnotia]
 description: Session handover — 2026/04/18 dogfooding sprint
 ---
 
-# Kon Handover — 2026/04/18
+# Magnotia Handover — 2026/04/18
 
 ## Current state
 
@@ -13,7 +13,7 @@ Phase 1 brand migration and Phase 2 polish are both **complete and committed**.
 
 ## What's working
 
-- **18/18 automated validation checks pass** (Playwright, `python3 /tmp/kon_validation.py`)
+- **18/18 automated validation checks pass** (Playwright, `python3 /tmp/magnotia_validation.py`)
 - **Pre-warm fixed** — `tauri::async_runtime::spawn` instead of `tokio::spawn`; model loads in background before first dictation
 - **Preferences infinite loop fixed** — `Object.assign` mutation instead of object reassignment; Svelte 5 module state now stable
 - **DOM hydration fixed** — `applyToDOM` called on store init so `data-theme` is always set, even without Tauri webview injection
@@ -32,7 +32,7 @@ sudo dnf install vulkan-headers vulkan-loader-devel glslc
 Then launch:
 
 ```bash
-cd /home/jake/Documents/CORBEL-Projects/kon
+cd /home/jake/Documents/CORBEL-Projects/magnotia
 LIBCLANG_PATH=/usr/lib64/llvm21/lib64 npm run tauri dev
 ```
 
@@ -49,7 +49,7 @@ Three items from the validation checklist that need real Tauri runtime:
 
 ### Pre-release (before any build beyond Jake's machine)
 - [ ] Updater signing key — `tauri signer generate`, public key → `tauri.conf.json`, private key → CI secrets
-- [ ] ggml dedup — plan at `docs/superpowers/plans/2026-04-18-kon-ggml-dedup.md`, Option A (system-ggml shared lib), execute at Phase 3
+- [ ] ggml dedup — plan at `docs/superpowers/plans/2026-04-18-magnotia-ggml-dedup.md`, Option A (system-ggml shared lib), execute at Phase 3
 
 ## Gotchas discovered today
 
@@ -64,7 +64,7 @@ Three items from the validation checklist that need real Tauri runtime:
 ## Resume prompt
 
 ```
-Picking up Kon dogfooding from the 2026/04/18 session.
+Picking up Magnotia dogfooding from the 2026/04/18 session.
 HANDOVER is at HANDOVER.md in the project root.
 First job: confirm Vulkan GPU build compiles and check startup logs for RTX 4070.
 Then run the three manual validation items from the handover.