agent: lumotia-rebrand — frontend strings (svelte + i18n + design-system)

Phase 8 of the rebrand cascade. Every rendered string is now Lumotia;
no Magnotia surface visible in the UI.

Sweep replaced \bmagnotia\b -> lumotia and \bMagnotia\b -> Lumotia
across all .svelte / .ts / .js / .css / .html / .json (excluding
package-lock.json which regenerates, target/, build/, node_modules/).

Surfaces touched:
- src/app.css — design-token comment header and .magnotia-rh-* CSS
  resize-handle class selectors (also the consuming elements in
  components/ResizeHandles.svelte and src/routes/*/+layout.svelte).
- src/lib/i18n/locales/{en,de,es}.json — brand name in translations.
- src/lib/i18n/index.ts — header comment.
- src/lib/Sidebar.svelte and most pages under src/lib/pages/ +
  src/lib/components/ — title bars, document titles, default
  filenames (lumotia-YYYY-MM-DD.* etc), toast strings, error
  messages, dialog headers.
- src/routes/+layout.svelte, +page.svelte, viewer/, float/, preview/.
- src/app.html page <title>.
- src/lib/utils/settingsMigrations.ts — fallback toast copy.
- src/design-system/{colors_and_type.css,SKILL.md,README.md,
  ui_kits/{Sidebar.jsx,index.html}} — design-tokens, doc strings,
  preview wordmark in the kit.
- package.json — name + description.

NOT touched (deferred / immutable):
- package-lock.json — regenerates on next npm install.
- The two migration-call sites in stores reference the legacy magnotia
  keys deliberately; restored after the sweep clobbered them.
- docs/, README.md, HANDOVER.md — Phase 9 scope.

npm run check: 0 errors / 0 warnings (3958 files).
cargo test --workspace: 339 pass / 0 fail.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/routes/+layout.svelte

@@ -42,7 +42,7 @@
   const prefs = getPreferences();
   const tauriRuntimeAvailable = hasTauriRuntime();
 
-  // On Linux Magnotia uses native KWin/Mutter decorations (see
+  // On Linux Lumotia uses native KWin/Mutter decorations (see
   // src-tauri/tauri.linux.conf.json and windows.rs). Frameless custom
   // chrome stays for macOS and Windows. Default to false so Linux users
   // don't see a flash of custom titlebar before loadOsInfo resolves.
@@ -68,7 +68,7 @@
   });
 
   // Global hotkey registration — dual backend
-  // Wayland: evdev via magnotia-hotkey crate (works without display server)
+  // Wayland: evdev via lumotia-hotkey crate (works without display server)
   // X11/macOS/Windows: tauri-plugin-global-shortcut (native)
   let registeredHotkey = null;
   let hotkeyBackend = $state("unknown"); // "evdev" | "tauri" | "unavailable"
@@ -356,7 +356,7 @@
     invoke("check_for_update")
       .then((version) => {
         if (version) {
-          toasts.info(`Magnotia ${version} is available. Download and restart to update.`);
+          toasts.info(`Lumotia ${version} is available. Download and restart to update.`);
         }
       })
       .catch(() => { /* update check failure must not affect the app */ });
@@ -473,7 +473,7 @@
      in the bottom-right of the viewport. (Day 3 of the upgrade plan) -->
 <ToastViewport />
 
-<!-- Global focus-timer overlay. Renders nothing until a `magnotia:start-timer`
+<!-- Global focus-timer overlay. Renders nothing until a `lumotia:start-timer`
      event fires; then pins a shrinking colour ring to the top-right.
      Phase 1 of the 2026-04-23 feature-complete roadmap — closes the
      visual-time-representation gap from docs/brief/feature-set.md and