feat: read "Занятия в Полоцке" as a day's town, show it in all clients

- Parser 14 (server/places.js): "Занятия в Полоцке/Новополоцке/г. Новополоцк" over a day's first row is no longer a lesson but a note of the day for its column (`places`); lessons of that day get `place`. A lesson below the note in the same cell keeps its own subject.
- A town on its own line ("Новополоцк", "г.Новополоцк") or after a room ("246(Новополоцк)") becomes the lesson's `place` and leaves the subject and room. "История Полоцка" is not a town.
- API 14: `place` on lessons and `places` on days of /api/timetable, `place` in the directory. The day notes are shared by the server and the PWA (shared/places.js); the same note in every subgroup reads as the whole group's.
- Android, PWA and iOS: a "Занятия в Полоцке" card above the day's lessons (day pages, calendar, overview, week view, desk stand), "Полоцк" under the date in the week grid, "249Ж · Полоцк" on lesson cards, a "Город" row in details, the town in widgets, tile, reminders and change lists.
- Snapshot lines show the town and the day notes; tests for notes, towns in cells and the API.

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

shared/places.js

@@ -0,0 +1,34 @@
+// "Занятия в Полоцке": Word marks the days a group spends in another town over the day's first
+// row; the parser keeps them as notes of the day (server/places.js). The notes of a day for one
+// group, shared by the server's timetable and the browser.
+
+/**
+ * The notes on a weekday (or a date) of the group: `{place, text, subgroup}`, the subgroup null
+ * for the whole group. The same note in every subgroup (`labels`) is the whole group's.
+ */
+export function placesOn(places, group, labels, day, date = null) {
+  const on = (places || [])
+    .filter((p) => p.groups.includes(group) && p.day === day && (!p.date || p.date === date))
+    .map((p) => ({ place: p.place, text: p.text, subgroup: p.subgroups.find((s) => s.group === group)?.label || null }));
+  const whole = on.filter((p) => !p.subgroup);
+  for (const p of on)
+    if (
+      p.subgroup &&
+      !whole.some((w) => w.text === p.text) &&
+      labels.length &&
+      labels.every((label) => on.some((o) => o.subgroup === label && o.text === p.text))
+    )
+      whole.push({ ...p, subgroup: null });
+  const parts = on.filter((p) => p.subgroup && !whole.some((w) => w.text === p.text));
+  return [...whole, ...parts].filter(
+    (p, i, all) => all.findIndex((o) => o.text === p.text && o.subgroup === p.subgroup) === i,
+  );
+}
+
+/** The notes for the student's subgroup; a note for their own subgroup reads as the whole day's. */
+export function placesFor(list, subgroup) {
+  return list
+    .filter((p) => !subgroup || !p.subgroup || p.subgroup === subgroup)
+    .map((p) => (subgroup ? { ...p, subgroup: null } : p))
+    .filter((p, i, all) => all.findIndex((o) => o.text === p.text && o.subgroup === p.subgroup) === i);
+}