refactor(tui): status icons, clean STATUS column, relative time

- STATUS column shows icon + clean state only (▲ UP, ▼ DOWN, ◆ LATE,
  ◆ STALE, ◇ PAUSED, ◼ MAINT, ○ PENDING). Error classification
  (DNS/TLS/TMO) removed from STATUS — stays in NAME inline hint.
- Detail panel Last Check shows relative time ("12s ago") instead of
  absolute timestamp.
- Extract shared fmtTimeAgo() to format.go, consolidate duplicate
  formatters in tab_alerts.go and tab_nodes.go.

internal/tui/format.go

@@ -152,33 +152,46 @@ func fmtRetries(site models.Site) string {
 	return s
 }
 
-func fmtStatus(status string, paused bool, inMaint bool, errCategory ErrorCategory) string {
+func fmtStatus(status string, paused bool, inMaint bool) string {
 	if paused {
-		return warnStyle.Render("PAUSED")
+		return warnStyle.Render("◇ PAUSED")
 	}
 	if inMaint {
-		return maintStyle.Render("MAINT")
+		return maintStyle.Render("◼ MAINT")
 	}
 	switch status {
 	case "DOWN":
-		label := "DOWN"
-		if errCategory != ErrCatUnknown {
-			label = "DOWN:" + string(errCategory)
-		}
-		return dangerStyle.Render(label)
+		return dangerStyle.Render("▼ DOWN")
 	case "SSL EXP":
-		return dangerStyle.Render(status)
+		return dangerStyle.Render("▼ SSL EXP")
 	case "LATE":
-		return warnStyle.Render(status)
+		return warnStyle.Render("◆ LATE")
 	case "STALE":
-		return staleStyle.Render(status)
+		return staleStyle.Render("◆ STALE")
 	case "PENDING":
-		return subtleStyle.Render(status)
+		return subtleStyle.Render("○ PENDING")
 	default:
-		return specialStyle.Render(status)
+		return specialStyle.Render("▲ " + status)
 	}
 }
 
+func fmtTimeAgo(t time.Time) string {
+	if t.IsZero() {
+		return subtleStyle.Render("never")
+	}
+	d := time.Since(t)
+	if d < time.Minute {
+		return fmt.Sprintf("%ds ago", int(d.Seconds()))
+	}
+	if d < time.Hour {
+		return fmt.Sprintf("%dm ago", int(d.Minutes()))
+	}
+	if d < 24*time.Hour {
+		return fmt.Sprintf("%dh ago", int(d.Hours()))
+	}
+	return fmt.Sprintf("%dd ago", int(d.Hours())/24)
+}
+
 func fmtDuration(d time.Duration) string {
 	if d < time.Minute {
 		return fmt.Sprintf("%ds", int(d.Seconds()))

internal/tui/format_test.go

@@ -55,32 +55,27 @@ func TestSiteOrder(t *testing.T) {
 	}
 }
 
-func TestFmtStatus_ErrorCategory(t *testing.T) {
+func TestFmtStatus(t *testing.T) {
 	tests := []struct {
 		status  string
 		paused  bool
 		inMaint bool
-		cat     ErrorCategory
 		wantSub string
 	}{
-		{"DOWN", false, false, ErrCatDNS, "DOWN:DNS"},
-		{"DOWN", false, false, ErrCatTLS, "DOWN:TLS"},
-		{"DOWN", false, false, ErrCatHTTP, "DOWN:HTTP"},
-		{"DOWN", false, false, ErrCatTCP, "DOWN:TCP"},
-		{"DOWN", false, false, ErrCatTimeout, "DOWN:TMO"},
-		{"DOWN", false, false, ErrCatICMP, "DOWN:ICMP"},
-		{"DOWN", false, false, ErrCatPrivate, "DOWN:PRIV"},
-		{"DOWN", false, false, ErrCatUnknown, "DOWN"},
-		{"UP", false, false, ErrCatUnknown, "UP"},
-		{"SSL EXP", false, false, ErrCatUnknown, "SSL EXP"},
-		{"DOWN", true, false, ErrCatDNS, "PAUSED"},
-		{"DOWN", false, true, ErrCatDNS, "MAINT"},
+		{"DOWN", false, false, "▼ DOWN"},
+		{"UP", false, false, "▲ UP"},
+		{"SSL EXP", false, false, "▼ SSL EXP"},
+		{"LATE", false, false, "◆ LATE"},
+		{"STALE", false, false, "◆ STALE"},
+		{"PENDING", false, false, "○ PENDING"},
+		{"DOWN", true, false, "◇ PAUSED"},
+		{"DOWN", false, true, "◼ MAINT"},
 	}
 	for _, tt := range tests {
-		got := fmtStatus(tt.status, tt.paused, tt.inMaint, tt.cat)
+		got := fmtStatus(tt.status, tt.paused, tt.inMaint)
 		if !containsPlain(got, tt.wantSub) {
-			t.Errorf("fmtStatus(%q, paused=%v, maint=%v, %q): %q missing %q",
-				tt.status, tt.paused, tt.inMaint, tt.cat, got, tt.wantSub)
+			t.Errorf("fmtStatus(%q, paused=%v, maint=%v): %q missing %q",
+				tt.status, tt.paused, tt.inMaint, got, tt.wantSub)
 		}
 	}
 }

internal/tui/tab_alerts.go

@@ -3,7 +3,6 @@ package tui
 import (
 	"fmt"
 	"strings"
-	"time"
 
 	"gitea.lerkolabs.com/lerkolabs/uptop/internal/monitor"
 	tea "github.com/charmbracelet/bubbletea"
@@ -146,20 +145,7 @@ func fmtAlertHealth(h monitor.AlertHealth) string {
 }
 
 func fmtAlertLastSent(h monitor.AlertHealth) string {
-	if h.LastSendAt.IsZero() {
-		return subtleStyle.Render("never")
-	}
-	d := time.Since(h.LastSendAt)
-	if d < time.Minute {
-		return fmt.Sprintf("%ds ago", int(d.Seconds()))
-	}
-	if d < time.Hour {
-		return fmt.Sprintf("%dm ago", int(d.Minutes()))
-	}
-	if d < 24*time.Hour {
-		return fmt.Sprintf("%dh ago", int(d.Hours()))
-	}
-	return fmt.Sprintf("%dd ago", int(d.Hours())/24)
+	return fmtTimeAgo(h.LastSendAt)
 }
 
 func (m Model) viewAlertsTab() string {

internal/tui/tab_nodes.go

@@ -1,7 +1,6 @@
 package tui
 
 import (
-	"fmt"
 	"time"
 )
 
@@ -66,15 +65,5 @@ func fmtNodeStatus(lastSeen time.Time) string {
 }
 
 func fmtNodeLastSeen(t time.Time) string {
-	if t.IsZero() {
-		return subtleStyle.Render("never")
-	}
-	ago := time.Since(t)
-	if ago < time.Minute {
-		return fmt.Sprintf("%ds ago", int(ago.Seconds()))
-	}
-	if ago < time.Hour {
-		return fmt.Sprintf("%dm ago", int(ago.Minutes()))
-	}
-	return fmt.Sprintf("%dh ago", int(ago.Hours()))
+	return fmtTimeAgo(t)
 }

internal/tui/tab_sites.go

@@ -128,7 +128,7 @@ func (m Model) viewSitesTab() string {
 						strconv.Itoa(i + 1),
 						m.zones.Mark(fmt.Sprintf("site-%d", i), icon+" "+limitStr(site.Name, nameW-4)),
 						"group",
-						fmtStatus(site.Status, site.Paused, m.isMonitorInMaintenance(site.ID), ErrCatUnknown),
+						fmtStatus(site.Status, site.Paused, m.isMonitorInMaintenance(site.ID)),
 						subtleStyle.Render("—"),
 						m.groupUptime(site.ID),
 						m.groupSparkline(site.ID, sparkWidth),
@@ -175,7 +175,7 @@ func (m Model) viewSitesTab() string {
 					strconv.Itoa(i + 1),
 					m.zones.Mark(fmt.Sprintf("site-%d", i), name),
 					typeIcon(site.Type, false) + " " + site.Type,
-					fmtStatus(site.Status, site.Paused, m.isMonitorInMaintenance(site.ID), classifyError(site.LastError, site.Type, site.StatusCode)),
+					fmtStatus(site.Status, site.Paused, m.isMonitorInMaintenance(site.ID)),
 					fmtLatency(site.Latency),
 					fmtUptime(hist.Statuses),
 					spark,

internal/tui/view_detail.go

@@ -41,8 +41,7 @@ func (m Model) viewDetailPanel() string {
 		b.WriteString("\n" + subtleStyle.Render("  "+label) + "\n")
 	}
 
-	errCat := classifyError(site.LastError, site.Type, site.StatusCode)
-	row("Status", fmtStatus(site.Status, site.Paused, m.isMonitorInMaintenance(site.ID), errCat))
+	row("Status", fmtStatus(site.Status, site.Paused, m.isMonitorInMaintenance(site.ID)))
 
 	if (site.Status == "DOWN" || site.Status == "SSL EXP" || site.Status == "LATE" || site.Status == "STALE") && site.LastError != "" {
 		errWidth := m.termWidth - chromePadH - 19
@@ -128,7 +127,7 @@ func (m Model) viewDetailPanel() string {
 	row("Latency", fmtLatency(site.Latency))
 	row("Uptime", fmtUptime(hist.Statuses))
 	if !site.LastCheck.IsZero() {
-		row("Last Check", site.LastCheck.Format("15:04:05"))
+		row("Last Check", fmtTimeAgo(site.LastCheck))
 	}
 
 	if site.Type == "http" {