Add subject options and redesign TV dashboard layout

Subject options:
- New subject_options table (auto-created on startup)
- SubjectOut now includes options list; all eager-loading chains updated
- Admin: Options panel per subject with add, inline edit, and delete
- WS broadcast and dashboard API include options in block subject data

TV dashboard:
- Three equal columns: Timer | Activities | Schedule
- Activities column shows current subject's options in large readable text
- Activities area has subject-colored border and tinted background
- Subject name and label displayed correctly using embedded subject data

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/components/ScheduleBlock.vue

@@ -10,7 +10,8 @@
     <div class="block-indicator" :style="{ background: subjectColor }"></div>
     <div class="block-body">
       <div class="block-title">
-        {{ block.label || subjectName || 'Block' }}
+        <span>{{ subjectName || block.label || 'Block' }}</span>
+        <span v-if="subjectName && block.label" class="block-label-suffix"> - {{ block.label }}</span>
       </div>
       <div class="block-time">
         {{ block.time_start }} – {{ block.time_end }}
@@ -108,6 +109,7 @@ const durationLabel = computed(() => {
   font-variant-numeric: tabular-nums;
 }
 
+.block-label-suffix { font-weight: 400; color: #94a3b8; }
 .block-duration { color: #475569; }
 .block-duration-custom { color: #818cf8; }