Consolidate duplicate utility functions into shared modules

Extract repeated helper functions from components into shared utils
(colors.ts, date.ts, file.ts) to reduce duplication:
- isLightColor, parseFilamentColor, hexToColorName → utils/colors.ts
- formatMediaTime, formatDurationFromHours → utils/date.ts
- formatFileSize guard hardened for NaN/negative → utils/file.ts
- formatBytes (ToastContext), formatTime (Timelapse*) deduplicated

Functions with subtly different behavior are intentionally kept local
(formatFilament, formatStorageSize, formatBytes, formatUptime,
formatDateTime, formatDate, formatTimeAgo) to preserve exact UI output.

frontend/src/utils/date.ts

@@ -418,3 +418,28 @@ export function formatRelativeTime(
   // Older than 7 days
   return formatDateTime(dateStr, timeFormat);
 }
+
+/**
+ * Format seconds as MM:SS for media/video player display.
+ *
+ * @param seconds - Total seconds
+ * @returns Formatted string (e.g., "2:05", "0:30")
+ */
+export function formatMediaTime(seconds: number): string {
+  const mins = Math.floor(seconds / 60);
+  const secs = Math.floor(seconds % 60);
+  return `${mins}:${secs.toString().padStart(2, '0')}`;
+}
+
+/**
+ * Format a duration given in hours to a human-readable string.
+ *
+ * @param hours - Duration in hours (e.g., 2.5)
+ * @returns Formatted string (e.g., "2h 30m", "45m", "3h")
+ */
+export function formatDurationFromHours(hours: number): string {
+  if (hours < 1) return `${Math.round(hours * 60)}m`;
+  const h = Math.floor(hours);
+  const m = Math.round((hours - h) * 60);
+  return m > 0 ? `${h}h ${m}m` : `${h}h`;
+}