feat(panel): CPU average window 15m -> 5m in panels and CLI

- Switch the CPU average window from -15m to -5m across admin/user panels
  and the CLI list/show path (mgr.List, mgr.Show, BatchUsers, PanelResources).
- Relabel the column/card to 5分钟CPU / 5m CPU.

The dashboard CPU figure now reflects the trailing 5-minute average.

src/internal/admin/templates/admin_overview.html

@@ -195,7 +195,7 @@ a.copy.copied { border-color: #86efac; background: #dcfce7; color: #15803d; }
           <th>{{if eq .Lang "zh"}}状态{{else}}State{{end}}</th>
           <th>{{if eq .Lang "zh"}}端口/SSH{{else}}Ports/SSH{{end}}</th>
           <th>{{if eq .Lang "zh"}}配额 CPU/内存/磁盘{{else}}Quota CPU/Mem/Disk{{end}}</th>
-          <th class="sortable" data-type="number">{{if eq .Lang "zh"}}15分钟CPU{{else}}15m CPU{{end}}<span class="ind"></span></th>
+          <th class="sortable" data-type="number">{{if eq .Lang "zh"}}5分钟CPU{{else}}5m CPU{{end}}<span class="ind"></span></th>
           <th class="sortable" data-type="number">{{if eq .Lang "zh"}}内存{{else}}Mem{{end}}<span class="ind"></span></th>
           <th class="sortable" data-type="number">{{if eq .Lang "zh"}}进程{{else}}Procs{{end}}<span class="ind"></span></th>
           <th class="sortable" data-type="number">{{if eq .Lang "zh"}}磁盘{{else}}Disk{{end}}<span class="ind"></span></th>
@@ -417,7 +417,7 @@ function del(name){
   var qc = document.getElementById('quotaCpu');
   if (qc) qc.addEventListener('input', function(){ syncCpuStep(qc); });
 })();
-// Clickable column headers for Name / 15m CPU / Mem / Procs / Disk: cycle
+// Clickable column headers for Name / 5m CPU / Mem / Procs / Disk: cycle
 // ascending -> descending -> default. Only one column sorts at a time; the
 // default state restores the original render order.
 (function(){

src/internal/mgr/batch.go

@@ -130,7 +130,7 @@ func readUptime() time.Duration {
 }
 
 // UserStatus is one row of the admin user table: the DB user record plus the
-// latest persisted resource sample and fifteen-minute CPU average.
+// latest persisted resource sample and five-minute CPU average.
 type UserStatus struct {
 	User     *db.User
 	State    string
@@ -154,7 +154,7 @@ func (m *Manager) BatchUsers() ([]*UserStatus, error) {
 	if err != nil {
 		return nil, err
 	}
-	average, err := m.db.AverageCPU(time.Now().Add(-15 * time.Minute).Unix())
+	average, err := m.db.AverageCPU(time.Now().Add(-5 * time.Minute).Unix())
 	if err != nil {
 		return nil, err
 	}

src/internal/mgr/mgr.go

@@ -716,7 +716,7 @@ func (m *Manager) List() ([]*Result, error) {
 		return nil, err
 	}
 	latest, _ := m.db.LatestResourceSamples()
-	average, _ := m.db.AverageCPU(time.Now().Add(-15 * time.Minute).Unix())
+	average, _ := m.db.AverageCPU(time.Now().Add(-5 * time.Minute).Unix())
 	live := m.liveStatusFallback(users, latest)
 	out := make([]*Result, 0, len(users))
 	for _, u := range users {
@@ -735,7 +735,7 @@ func (m *Manager) Show(name string) (*Result, error) {
 		return nil, err
 	}
 	latest, _ := m.db.LatestResourceSamples()
-	average, _ := m.db.AverageCPU(time.Now().Add(-15 * time.Minute).Unix())
+	average, _ := m.db.AverageCPU(time.Now().Add(-5 * time.Minute).Unix())
 	sample, hasSample := latest[u.ID]
 	live := m.liveStatusFallback([]*db.User{u}, latest)
 	avg, hasAverage := average[u.ID]

src/internal/mgr/resource.go

@@ -229,14 +229,14 @@ func decorateStoredUsage(r *Result, sample db.ResourceSample, hasSample bool, av
 }
 
 // PanelResources returns the persisted usage for a user's panel page: the
-// fifteen-minute CPU average and the latest memory/disk usage, formatted for
+// five-minute CPU average and the latest memory/disk usage, formatted for
 // display. No Incus call is made — the data comes from the background sampler.
 func (m *Manager) PanelResources(userID int64) (cpuUse, memUse, diskUse string) {
 	latest, err := m.db.LatestResourceSamples()
 	if err != nil {
 		return "-", "-", "-"
 	}
-	avg, err := m.db.AverageCPU(time.Now().Add(-15 * time.Minute).Unix())
+	avg, err := m.db.AverageCPU(time.Now().Add(-5 * time.Minute).Unix())
 	if err != nil {
 		avg = map[int64]float64{}
 	}

src/internal/panel/panel.go

@@ -311,7 +311,7 @@ func (s *Server) buildData(u *db.User, msg, errMsg string) pageData {
 		Msg:        msg,
 		Err:        errMsg,
 	}
-	// Resource usage comes from the persisted sampler snapshot (fifteen-minute
+	// Resource usage comes from the persisted sampler snapshot (five-minute
 	// CPU average plus latest memory/disk), never from a live Incus sample.
 	d.CPUUse, d.MemUse, d.DiskUsed = s.mgr.PanelResources(u.ID)
 	// One `incus list` call only for the container status (must be live).

src/internal/panel/templates/overview.html

@@ -196,7 +196,7 @@ footer a{color:var(--muted);text-decoration:underline}
 <div class="qitem"><span class="qlabel">{{if eq .Lang "zh"}}磁盘{{else}}Disk{{end}}</span><span class="qval">{{.QuotaDisk}}</span></div>
 </div>
 <div class="qgrid">
-<div class="qitem"><span class="qlabel">{{if eq .Lang "zh"}}15分钟CPU{{else}}15m CPU{{end}}</span><span class="qval">{{.CPUUse}}</span></div>
+<div class="qitem"><span class="qlabel">{{if eq .Lang "zh"}}5分钟CPU{{else}}5m CPU{{end}}</span><span class="qval">{{.CPUUse}}</span></div>
 <div class="qitem"><span class="qlabel">{{if eq .Lang "zh"}}已用内存{{else}}Mem used{{end}}</span><span class="qval">{{.MemUse}}</span></div>
 <div class="qitem"><span class="qlabel">{{if eq .Lang "zh"}}已用磁盘{{else}}Disk used{{end}}</span><span class="qval">{{.DiskUsed}}</span></div>
 </div>