IGDB integration: auto-scrape on upload + manual scrape button

- New IgdbService: Twitch OAuth2, IGDB API v4 search, cover download
- Upload auto-scrapes IGDB after extracting game ZIP
- GameDetail page: 'Auto Scrape' + 'Search' buttons + result picker
- Upload dialog: optional title field (defaults to filename)
- Jackson SNAKE_CASE naming to match frontend expectations
- IGDB status endpoint to check credentials

frontend/src/pages/Library.svelte

@@ -7,6 +7,7 @@
   let search = $state("");
   let uploading = $state(false);
   let uploadError = $state("");
+  let uploadTitle = $state("");
   let fileInput;
 
   async function loadGames() {
@@ -26,7 +27,8 @@
     uploading = true;
     uploadError = "";
     try {
-      await uploadGame(file);
+      await uploadGame(file, uploadTitle.trim() || undefined);
+      uploadTitle = "";
       await loadGames();
       fileInput.value = "";
     } catch (err) {
@@ -50,17 +52,26 @@
         bind:value={search}
         oninput={() => loadGames()}
       />
-      <label class="btn btn-primary upload-label">
-        {uploading ? "Uploading..." : "+ Upload Game"}
+      <div class="upload-group">
         <input
-          bind:this={fileInput}
-          type="file"
-          accept=".zip"
-          class="hidden-input"
-          onchange={handleUpload}
+          type="text"
+          class="title-input"
+          placeholder="Title (optional)"
+          bind:value={uploadTitle}
           disabled={uploading}
         />
-      </label>
+        <label class="btn btn-primary upload-label">
+          {uploading ? "Uploading..." : "+ Upload"}
+          <input
+            bind:this={fileInput}
+            type="file"
+            accept=".zip"
+            class="hidden-input"
+            onchange={handleUpload}
+            disabled={uploading}
+          />
+        </label>
+      </div>
     </div>
   </div>
 
@@ -111,15 +122,26 @@
     display: flex;
     gap: 12px;
     align-items: center;
+    flex-wrap: wrap;
   }
   .toolbar-actions input {
     min-width: 200px;
   }
+  .upload-group {
+    display: flex;
+    gap: 8px;
+    align-items: center;
+  }
+  .title-input {
+    min-width: 160px !important;
+    width: 160px;
+  }
   .hidden-input {
     display: none;
   }
   .upload-label {
     cursor: pointer;
+    white-space: nowrap;
   }
   .grid {
     display: grid;
@@ -162,4 +184,4 @@
     color: var(--text-dim);
     font-size: 0.85rem;
   }
-</style>
+</style>