Add HelpPanel and TodoItemTouch components, extend task commands, and refactor task and view logic

- Introduced `HelpPanel.vue` for displaying keyboard shortcuts and command descriptions.
- Added `TodoItemTouch.vue`, a mobile-friendly task item component with updated bindings and improved actions.
- Extended task commands with support for tagging, due date parsing, and dynamic text formatting.
- Implemented `useActions` utility for parsing and executing command-based task modifications.
- Streamlined task editing and creation in `useTasks` for consistency and API integration.
- Updated `ListScreen` to support collapsible, categorized task lists with visual enhancements.
- Refactored `App.vue` for adaptive input handling on mobile versus desktop views.
- Enhanced API communication in `useApi` with cleaner header generation and error handling.

src/utils/helpers.ts

@@ -0,0 +1,27 @@
+import type { Task } from '../types.ts'
+import Sherlock from 'sherlockjs'
+
+export function parseDueDate(text: string): number | null {
+  try {
+    const parsed = Sherlock.parse(text)
+    if (parsed && parsed.startDate) {
+      return parsed.startDate.getTime()
+    }
+  }
+  catch {}
+  const ts = Date.parse(text)
+  return Number.isNaN(ts) ? null : ts
+}
+
+export function stopWorkLogging(t: Task) {
+  if (t.logs && t.logs.length) {
+    const lastLog = t.logs[t.logs.length - 1]
+    if (lastLog.start && !lastLog.end) {
+      lastLog.end = Date.now()
+    }
+  }
+  else {
+    t.logs = []
+  }
+  return t
+}