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>

notes.js

@@ -46,7 +46,7 @@ async function handle(req, res) {
     if ((m = /^\/([0-9a-f]{12})$/.exec(p)) && req.method === 'DELETE') { const n = find(m[1], me, true); cache = all().filter(x => x !== n); save(); return json(res, 200, { ok: true }); }
     if ((m = /^\/([0-9a-f]{12})\/items$/.exec(p)) && req.method === 'POST') { // one change to a checklist
       const n = find(m[1], me); if (n.type !== 'list') throw fail(400, 'That is not a checklist'); const b = JSON.parse(await readBody(req, 2e4) || '{}'), it = id => n.items.find(x => x.id === String(id));
-      if (b.text !== undefined && !b.edit) { const t = str(b.text, 300).trim(); if (!t) throw fail(400, 'Write the item'); if (n.items.length >= MAX_ITEMS) throw fail(400, 'That is a long list'); n.items.push({ id: newId(), text: t, done: false }); }
+      if (b.text !== undefined && !b.edit) { const t = str(b.text, 300).trim(); if (!t) throw fail(400, 'Write the item'); if (n.items.length >= MAX_ITEMS) throw fail(400, 'That is a long list'); n.items.push({ id: newId(), text: t, done: false, addedBy: me.name }); }
       else if (b.toggle) { const x = it(b.toggle); if (!x) throw fail(404, 'Item not found'); x.done = !!b.done; if (x.done) { x.by = me.id; x.byName = me.name; x.at = Date.now(); } else { delete x.by; delete x.byName; delete x.at; } }
       else if (b.edit) { const x = it(b.edit), t = str(b.text, 300).trim(); if (!x || !t) throw fail(400, 'Write the item'); x.text = t; }
       else if (b.remove) n.items = n.items.filter(x => x.id !== String(b.remove));