Family board: add to shopping, tasks, checklists and the Family calendar; record who added each

- + button on each board card: write it, tap your name (PIN unless a child), it is added as you
- Tasks, events, checklist items and shopping items remember who added them
- Names shown on the board and in Tasks, Notes and Calendar
- Tests and README updated

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

public/tasks.js

@@ -48,7 +48,7 @@ async function loadTaskList(cur, list) {
     const done = tasks.filter(t => top(t) && t.done).sort((a, b) => (b.completedAt || 0) - (a.completedAt || 0) || a.title.localeCompare(b.title));
     const REPEAT_LABEL = { daily: 'Daily', weekdays: 'Weekdays', weekly: 'Weekly', monthly: 'Monthly', yearly: 'Yearly' };
     const row = (t, sub) => { const i = taskStore.push(t) - 1, du = dueInfo(t.due), kids = byParent[t.id] || [], rep = REPEAT_LABEL[t.repeat], prog = kids.length ? kids.filter(k => k.done).length + '/' + kids.length + ' subtasks' : '';
-      const extra = [all && t._ln ? t._ln : '', rep ? '↻ ' + rep : '', prog].filter(Boolean).join(' · ');
+      const extra = [all && t._ln ? t._ln : '', t.by && t.list === 'local:family' ? 'Added by ' + t.by : '', rep ? '↻ ' + rep : '', prog].filter(Boolean).join(' · ');
       return `<div class="row it${t.done ? ' donetask' : ''}${sub ? ' subtask' : ''}"><button class="ibtn tick" data-t="${i}" aria-label="${t.done ? 'Mark not done' : 'Mark done'}">${icon('check')}</button>
         <button class="rmain" data-e="${i}"><span class="grow"><b>${esc(t.title)}</b>${du || t.notes || extra ? `<small>${du ? `<span style="color:${du.color}">${esc(du.text)}</span>` : ''}${du && (extra || t.notes) ? ' · ' : ''}${esc(extra)}${extra && t.notes ? ' · ' : ''}${esc((t.notes || '').split('\n')[0])}</small>` : ''}</span></button></div>`; };
     const showDone = store.get('task_show_done', false);