feat: add SettingsPage with HuggingFace model search and fix flexbox layout

- Add SettingsPage component with macOS/Linear-style settings UI (sp-* classes)
- Fix HuggingFace results list squeeze: sp-card-row--full now has align-items: stretch
  overriding the inherited flex-start, ensuring children fill 100% horizontal width
- Fix sp-hf-file row layout: width 100%, grid columns for name/quant/size/download
- Fix sp-hf-name truncation: explicit overflow/ellipsis/white-space in CSS
- Add white-space: nowrap to sp-hf-size and sp-hf-quant-badge to protect secondary columns
- Add runtime-deps crate, Tailwind/PostCSS config, runtime-defaults, MessageBubble test
- Update Cargo workspace, inference-server, tauri runtime types and process handling

tauri-app/src/App.tsx

@@ -1,6 +1,7 @@
 import { useState, useEffect, useCallback } from "react";
 import Sidebar from "./components/Sidebar";
 import ChatView from "./components/ChatView";
+import SettingsPage from "./features/settings/SettingsPage";
 import { useDB } from "./hooks/useDB";
 import { useModels } from "./hooks/useModels";
 import { useRuntimeManager } from "./features/runtime/useRuntimeManager";
@@ -13,6 +14,7 @@ export default function App() {
   const [currentChatId, setCurrentChatId] = useState<number | null>(null);
   const [chats, setChats] = useState<Chat[]>([]);
   const [sidebarOpen, setSidebarOpen] = useState(false);
+  const [view, setView] = useState<"chat" | "settings">("chat");
 
   const runtime = useRuntimeManager();
   const { models, selectedModel, setSelectedModel, status, refresh: refreshModels } = useModels(
@@ -65,22 +67,24 @@ export default function App() {
   }
 
   return (
-    <div className={`app-layout${sidebarOpen ? " sidebar-open" : ""}`}>
-      <Sidebar
-        chats={chats}
-        currentChatId={currentChatId}
-        onSelectChat={handleSelectChat}
-        onNewChat={newChat}
-        onDeleteChat={deleteChat}
-        models={models}
-        selectedModel={selectedModel}
-        onModelChange={setSelectedModel}
-        status={status}
-        onRefreshModels={refreshModels}
-        runtime={runtime}
-        onCloseMobile={() => setSidebarOpen(false)}
-      />
-      {sidebarOpen && (
+    <div className={`app-layout${sidebarOpen && view !== "settings" ? " sidebar-open" : ""}`}>
+      {view !== "settings" && (
+        <Sidebar
+          chats={chats}
+          currentChatId={currentChatId}
+          onSelectChat={handleSelectChat}
+          onNewChat={newChat}
+          onDeleteChat={deleteChat}
+          models={models}
+          selectedModel={selectedModel}
+          onModelChange={setSelectedModel}
+          status={status}
+          onRefreshModels={refreshModels}
+          onOpenSettings={() => setView("settings")}
+          onCloseMobile={() => setSidebarOpen(false)}
+        />
+      )}
+      {view !== "settings" && sidebarOpen && (
         <button
           type="button"
           className="app-sidebar-backdrop"
@@ -89,16 +93,20 @@ export default function App() {
         />
       )}
       <div className="app-main">
-        <ChatView
-          db={db!}
-          chatId={currentChatId}
-          server={runtime.connection.serverUrl}
-          apiKey={runtime.connection.apiKey}
-          model={selectedModel}
-          onChatCreated={(id) => { setCurrentChatId(id); loadChats(); setSidebarOpen(false); }}
-          onChatUpdated={loadChats}
-          onOpenSidebar={() => setSidebarOpen(true)}
-        />
+        {view === "settings" ? (
+          <SettingsPage runtime={runtime} onClose={() => setView("chat")} />
+        ) : (
+          <ChatView
+            db={db!}
+            chatId={currentChatId}
+            server={runtime.connection.serverUrl}
+            apiKey={runtime.connection.apiKey}
+            model={selectedModel}
+            onChatCreated={(id) => { setCurrentChatId(id); loadChats(); setSidebarOpen(false); }}
+            onChatUpdated={loadChats}
+            onOpenSidebar={() => setSidebarOpen(true)}
+          />
+        )}
       </div>
     </div>
   );