fix(approvals): show — instead of 0m·0 tasks for pending/disapproved sheets

approvedSnapshot is only populated at approval time; pending and disapproved
sheets had null snapshot so the card always displayed 0m · 0 tasks.

Now totalSecs/taskCount are passed as nullable params from the parent; the
card renders — when no snapshot is available yet.

Also accept camelCase 'daySheets' URL param in parseProgrammerTasksTab
alongside the existing hyphenated 'day-sheets' spelling.

Co-Authored-By: claude-flow <ruv@ruv.net>

lib/screens/programmer_tasks/programmer_tasks_tabs.dart

@@ -42,6 +42,7 @@ ProgrammerTasksTab? parseProgrammerTasksTab(String? q) {
     case 'all':
       return ProgrammerTasksTab.all;
     case 'day-sheets':
+    case 'daySheets':
       return ProgrammerTasksTab.daySheets;
     default:
       return null;