fix: SkillsUsage 页面样式修复与 API server skill usage 统计 (#698)

* Reapply "feat: 新增 Skills Usage 监控统计与图表 (#668)" (#670)

This reverts commit 91de3b12a1.

* fix: count API-server skill usage

* fix: align SkillsUsageView header with other pages and update sidebar icon

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

---------

Co-authored-by: Zhicheng Han <zhicheng.han@mathematik.uni-goettingen.de>
Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>

packages/client/src/i18n/locales/en.ts

@@ -83,6 +83,7 @@ export default {
     memory: 'Memory',
     logs: 'Logs',
     usage: 'Usage',
+    skillsUsage: 'Skills Usage',
     channels: 'Channels',
     gateways: 'Gateways',
     terminal: 'Terminal',
@@ -985,6 +986,28 @@ export default {
     cost: 'Cost',
     noData: 'No usage data',
   },
+  skillsUsage: {
+    title: 'Skills Usage',
+    subtitle: 'Track skill loads and edits from Hermes sessions',
+    refresh: 'Refresh',
+    periodSelector: 'Skill usage period',
+    periodLabel: '{days}d',
+    summary: 'Summary',
+    totalActions: 'Actions',
+    loads: 'Loads',
+    edits: 'Edits',
+    distinctSkills: 'Skills',
+    topSkills: 'Top Skills',
+    dailyTrend: 'Daily Trend',
+    periodSummary: 'Last {days} days',
+    skill: 'Skill',
+    share: 'Share',
+    lastUsed: 'Last Used',
+    noData: 'No skill usage data',
+    loadFailed: 'Failed to load skill usage',
+    otherSkills: 'Other skills',
+  },
+
   // Files
   files: {
     title: 'Files',