feat: 实现域能系统

- 新增域能完整分层：EnergyLog/PostEnergizeLog/DailyExpSummary 模型、EnergyRepo、EnergyService、EnergyController/AdminEnergyController
- 支持签到获取域能(+1)、帖子赋能(-1/-2)/被赋能(+1/+2)、改名扣能(-6)/退款(+6)、删帖扣能(-2)
- 赋能单人单帖上限20域能，每日赋能获得经验上限50
- 管理员支持批量调整域能(owner)和查询域能日志(admin)
- LV0用户(exp<1)禁止签到和发帖，余额为负可签到/被赋能/删帖但不能赋能/改名
- 首次改名免费(通过HasCompletedTask判重)，改名扣能在提交审核时执行
- 移除导航栏手动签到按钮，签到融入域能系统(自动签到)
- 新增个人中心域能TAB展示余额和流水日志(近7天)
- 新增帖子详情页赋能按钮(轻赋/重赋)
- 管理后台新增域能管理和域能日志页面

templates/MetaLab-2026/static/css/settings.css

@@ -783,3 +783,97 @@ body {
         max-width: 100%;
     }
 }
+
+/* ---------- Energy Tab ---------- */
+.energy-summary {
+    display: flex;
+    gap: 1.5rem;
+    padding: 1rem 0;
+    border-bottom: 1px solid #f0f0f0;
+    margin-bottom: 1rem;
+}
+
+.energy-stat {
+    display: flex;
+    flex-direction: column;
+    gap: .25rem;
+}
+
+.energy-label {
+    font-size: .82rem;
+    color: var(--color-text-light);
+    font-weight: 500;
+}
+
+.energy-value {
+    font-size: 1.25rem;
+    font-weight: 700;
+    color: var(--color-accent);
+}
+
+.energy-log-list {
+    display: flex;
+    flex-direction: column;
+}
+
+.energy-log-empty {
+    text-align: center;
+    padding: 2rem 0;
+    color: #bbb;
+    font-size: .9rem;
+}
+
+.energy-log-item {
+    display: flex;
+    flex-direction: column;
+    gap: .3rem;
+    padding: .85rem 0;
+    border-bottom: 1px solid #f5f5f5;
+}
+
+.energy-log-item:last-child {
+    border-bottom: none;
+}
+
+.energy-log-meta {
+    display: flex;
+    justify-content: space-between;
+    align-items: center;
+}
+
+.energy-log-type {
+    font-size: .85rem;
+    font-weight: 600;
+    color: var(--color-text);
+}
+
+.energy-log-time {
+    font-size: .78rem;
+    color: #aaa;
+}
+
+.energy-log-info {
+    display: flex;
+    justify-content: space-between;
+    align-items: center;
+}
+
+.energy-log-desc {
+    font-size: .82rem;
+    color: var(--color-text-light);
+}
+
+.energy-log-amount {
+    font-size: .88rem;
+    font-weight: 600;
+    white-space: nowrap;
+    margin-left: 1rem;
+}
+
+.energy-log-plus .energy-log-amount {
+    color: #2ecc71;
+}
+
+.energy-log-minus .energy-log-amount {
+    color: #e74c3c;
+}