feat(gui): wire Footer + Settings to daemon over IPC (closes the gap from a6a098d)

a6a098d added daemon-side IPC handlers (SwitchLlm, ReloadLlm, QueryHealth)
but the GUI was still talking only to its own process. This commit wires
the frontend to actually use those handlers.

frontend/src/lib/ipc.ts
  - New DaemonHealth interface + daemonHealth: writable<DaemonHealth | null>.
  - handleEvent: "health_snapshot" case fills daemonHealth from daemon's IpcEvent.
  - New senders:
      switchDaemonLlm(backend)  → action "switch_llm"
      reloadDaemonLlm()          → action "reload_llm"
      queryDaemonHealth()        → action "query_health"

frontend/src/stores.ts
  - Re-exports daemonHealth + the three new senders + DaemonHealth type.

frontend/src/components/Footer.svelte
  - Polls every 5s but PREFERS IPC: if daemon connected, calls queryDaemonHealth
    (snapshot arrives via daemonHealth store).
  - Falls back to invoke("get_active_backends") if daemon offline — shows
    GUI-process view in that case, with the chip tooltip distinguishing
    "daemon" vs "gui-process" source.

frontend/src/routes/settings/index.svelte (AI Backends tab)
  - applyLlmBackend now ALSO fires switchDaemonLlm so the running listener
    picks the new backend without restart.
  - "Auto" (empty) path calls reloadDaemonLlm so daemon re-reads DB.

End-to-end flow now:
  GUI dropdown → set_llm_backend (Tauri, persists DB + swaps GUI proc)
              ↘ switchDaemonLlm (IPC, swaps daemon proc too)
              ↘ daemon emits health_snapshot on next QueryHealth
              ↘ daemonHealth store updates
              ↘ Footer chips re-render with new state

Build: cargo build --release -p jarvis-gui green.

frontend/src/routes/settings/index.svelte

@@ -5,7 +5,10 @@
     import { setTimeout } from "worker-timers"
 
     import { showInExplorer } from "@/functions"
-    import { appInfo, assistantVoice, translations, translate } from "@/stores"
+    import {
+        appInfo, assistantVoice, translations, translate,
+        switchDaemonLlm, reloadDaemonLlm,
+    } from "@/stores"
 
     import HDivider from "@/components/elements/HDivider.svelte"
     import Footer from "@/components/Footer.svelte"
@@ -113,6 +116,7 @@
         if (target === "") {
             try {
                 await invoke("db_write", { key: "llm_backend", val: "" })
+                reloadDaemonLlm() // tell daemon to re-read DB (now auto)
             } catch (err) {
                 backendSwapError = String(err)
             }
@@ -121,7 +125,11 @@
         }
         backendSwapBusy = true
         try {
+            // 1. Swap on GUI process (persists to DB).
             await invoke<string>("set_llm_backend", { name: target })
+            // 2. Tell daemon to swap too, so the running listener uses the
+            //    new backend immediately. No-op if daemon not connected.
+            switchDaemonLlm(target as "groq" | "ollama")
             await refreshActiveBackends()
         } catch (err) {
             backendSwapError = String(err)