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/routes/+layout.svelte

@@ -0,0 +1,98 @@
+<script>
+  import "../app.css";
+  import { onDestroy } from "svelte";
+  import Sidebar from "$lib/Sidebar.svelte";
+  import TaskSidebar from "$lib/components/TaskSidebar.svelte";
+  import Titlebar from "$lib/components/Titlebar.svelte";
+  import { page, settings } from "$lib/stores/page.svelte.js";
+
+  let { children } = $props();
+
+  // Recording indicator dot (follows mouse)
+  let mouseX = $state(0);
+  let mouseY = $state(0);
+
+  function handleMouseMove(e) {
+    mouseX = e.clientX;
+    mouseY = e.clientY;
+  }
+
+  // Theme application
+  $effect(() => {
+    const theme = settings.theme;
+    if (theme === "Light") {
+      document.documentElement.classList.add("light");
+      return;
+    }
+    if (theme === "Dark") {
+      document.documentElement.classList.remove("light");
+      return;
+    }
+    // System mode
+    const mq = window.matchMedia("(prefers-color-scheme: light)");
+    const apply = () => document.documentElement.classList.toggle("light", mq.matches);
+    apply();
+    mq.addEventListener("change", apply);
+    return () => mq.removeEventListener("change", apply);
+  });
+
+  // Global hotkey registration
+  let registeredHotkey = null;
+
+  async function registerGlobalHotkey(hotkey) {
+    try {
+      const mod = await import("@tauri-apps/plugin-global-shortcut");
+      if (registeredHotkey) {
+        await mod.unregister(registeredHotkey).catch(() => {});
+      }
+      await mod.register(hotkey, () => {
+        if (page.current !== "dictation") page.current = "dictation";
+        requestAnimationFrame(() => {
+          window.dispatchEvent(new CustomEvent("ramble:toggle-recording"));
+        });
+      });
+      registeredHotkey = hotkey;
+    } catch (err) {
+      console.error("Hotkey registration failed:", err);
+    }
+  }
+
+  $effect(() => {
+    registerGlobalHotkey(settings.globalHotkey);
+  });
+
+  // Apply font size setting as CSS variable
+  $effect(() => {
+    document.documentElement.style.setProperty("--font-size-transcript", `${settings.fontSize}px`);
+  });
+
+  onDestroy(() => {
+    if (registeredHotkey) {
+      import("@tauri-apps/plugin-global-shortcut")
+        .then((mod) => mod.unregister(registeredHotkey))
+        .catch(() => {});
+    }
+  });
+</script>
+
+<svelte:window onmousemove={handleMouseMove} />
+
+{#if page.recording}
+  <div
+    class="fixed w-3 h-3 rounded-full bg-danger animate-pulse-soft pointer-events-none"
+    style="left: {mouseX + 18}px; top: {mouseY + 18}px; z-index: 100;"
+  ></div>
+{/if}
+
+<div class="flex flex-col h-screen w-screen overflow-hidden grain">
+  <Titlebar />
+  <div class="flex flex-1 min-h-0">
+    <Sidebar />
+    <div class="flex-1 overflow-hidden bg-bg">
+      {@render children()}
+    </div>
+    {#if page.taskSidebarOpen}
+      <TaskSidebar />
+    {/if}
+  </div>
+</div>