feat(ui): profile picker + per-profile vocabulary; transcribe invokes carry profileId; drop buildInitialPrompt

src/lib/pages/DictationPage.svelte

@@ -3,6 +3,7 @@
   import { onMount, onDestroy } from "svelte";
   import { Channel, invoke } from "@tauri-apps/api/core";
   import { page, settings, templates, profiles, addToHistory, addTask, tasks } from "$lib/stores/page.svelte.js";
+  import { profilesStore } from "$lib/stores/profiles.svelte.ts";
   import { toasts } from "$lib/stores/toasts.svelte.js";
   import Card from "$lib/components/Card.svelte";
   import ModelDownloader from "$lib/components/ModelDownloader.svelte";
@@ -123,18 +124,6 @@
     return currentModelIsEnglishOnly() ? "en" : settings.language;
   }
 
-  function buildInitialPrompt() {
-    if (!page.activeProfile || page.activeProfile === "None") return "";
-    const profile = profiles.find((entry) => entry.name === page.activeProfile);
-    if (!profile?.words) return "";
-    const words = profile.words
-      .split("\n")
-      .map((word) => word.trim())
-      .filter(Boolean);
-    if (words.length === 0) return "";
-    return `Use these terms when they match the audio: ${words.join(", ")}`;
-  }
-
   async function refreshRuntimeCapabilities() {
     runtimeCapabilities = await invoke("get_runtime_capabilities");
   }
@@ -322,7 +311,11 @@
           engine: settings.engine,
           modelId: selectedModelId(),
           language: effectiveLanguage(),
-          initialPrompt: buildInitialPrompt(),
+          // Backend (Task 13) falls back to profile.initial_prompt when this
+          // is empty. Vocabulary now lives on the active profile, not on the
+          // old page.activeProfile localStorage bag.
+          initialPrompt: "",
+          profileId: profilesStore.activeProfileId,
           saveAudio: settings.saveAudio,
           outputFolder: settings.outputFolder || null,
           removeFillers: settings.removeFillers,