ui(prores): move prores_mode toggle next to prores_profile on VideoToolbox tab

The experimental ProRes mode selector landed in the generic Advanced
tab while prores_profile (its inseparable companion — the mode toggle
only makes sense if you also pick a profile) lived on the
VideoToolbox Encoder tab. Splitting the two knobs across tabs hurts
discoverability: users configuring VideoToolbox don't realise ProRes
exists, and users on the Advanced tab can't see the profile that
controls bit depth and chroma subsampling.

Move prores_mode into VideoToolboxEncoder.vue directly above
prores_profile so both controls sit together in their codec-relevant
section. The macOS-only platform guard previously around prores_mode
in Advanced.vue is implicit on the VideoToolbox tab (which is itself
macOS-only), so it can be dropped.

No backend or config change; pure UI relocation.

Author: Nottlespike

src_assets/common/assets/web/configs/tabs/Advanced.vue

@@ -58,17 +58,6 @@ const config = ref(props.config)
       <div class="form-text">{{ $t('config.av1_mode_desc') }}</div>
     </div>
 
-    <!-- Experimental ProRes Support -->
-    <div class="mb-3" v-if="platform === 'macos'">
-      <label for="prores_mode" class="form-label">{{ $t('config.prores_mode') }}</label>
-      <select id="prores_mode" class="form-select" v-model="config.prores_mode">
-        <option value="0">{{ $t('config.prores_mode_0') }}</option>
-        <option value="1">{{ $t('config.prores_mode_1') }}</option>
-        <option value="2">{{ $t('config.prores_mode_2') }}</option>
-      </select>
-      <div class="form-text">{{ $t('config.prores_mode_desc') }}</div>
-    </div>
-
     <!-- Capture -->
     <div class="mb-3" v-if="platform !== 'macos'">
       <label for="capture" class="form-label">{{ $t('config.capture') }}</label>

src_assets/common/assets/web/configs/tabs/encoders/VideotoolboxEncoder.vue

@@ -37,6 +37,17 @@ const config = ref(props.config)
               v-model="config.vt_realtime"
               default="true"
     ></Checkbox>
+
+    <!-- Experimental ProRes Support -->
+    <div class="mb-3">
+      <label for="prores_mode" class="form-label">{{ $t('config.prores_mode') }}</label>
+      <select id="prores_mode" class="form-select" v-model="config.prores_mode">
+        <option value="0">{{ $t('config.prores_mode_0') }}</option>
+        <option value="1">{{ $t('config.prores_mode_1') }}</option>
+        <option value="2">{{ $t('config.prores_mode_2') }}</option>
+      </select>
+      <div class="form-text">{{ $t('config.prores_mode_desc') }}</div>
+    </div>
     <div class="mb-3">
       <label for="prores_profile" class="form-label">{{ $t('config.prores_profile') }}</label>
       <select id="prores_profile" class="form-select" v-model="config.prores_profile">