Read the user's own lesson notes, and the class register behind them

Schulcloud says what was uploaded and WebUntis says what was scheduled.
Neither says what was *taught* — which point the teacher laboured, which
example landed, what "will definitely come up". That lives in two places
this server could not reach: the notes the user takes in the lesson, and
WebUntis' class register.

Notes are a directory of Markdown files (NOTES_DIR), not a table. They
have to be writable from a phone in a classroom, readable when Postgres
is down, and outlive this project, and files are the only shape that is
all three — so the files are the truth and the index is a view of them,
the same split as file_texts and the mirror. list_notes and get_note read
disk, so they answer before the first crawl; search, what_changed and all
three German prompts read them alongside the Schulcloud material.

add_note writes one, and is the only thing in this server that writes
anything. That is not a hole in the read-only invariant but a different
store: it is bounded to NOTES_DIR by the same safeComponent/resolveWithin
pair that stops a hostile Schulcloud filename escaping the mirror, so a
note titled ../../.ssh/authorized_keys becomes a filename. Schulcloud and
WebUntis stay GET-only and allowlisted respectively. NOTES_READONLY
refuses writes outright.

Appending targets the *lesson*, not the title: "halt das auch noch fest"
mid-lesson carries a new title, and deriving the path from it would start
a second note every time, which is the one thing append exists to prevent.

Notes.app has no export — its bodies are compressed protobuf and the
iCloud copy is encrypted — so scripting the app is not the clumsy route
to the notes but the only one. scripts/export-apple-notes.js reads them
through AppleScript into one JSON object per line, and `schulcloud note
import` converts the HTML to Markdown, takes the Notes folder as the
subject and the *creation* date as the lesson's date. Attachments cannot
come across; a note that was a photo of the board imports as a line
saying so, because importing it empty would hide the loss.

The class register needed one API property to become cheap:
getLessonTopic2017 answers per *series*, not per period, so a term is
reconstructed by asking about the latest period of each lesson series and
merging back by id — a few dozen calls for a school year rather than one
per lesson. untis_lesson_topics now takes a subject as well as a period
id, and UNTIS_HISTORY_DAYS of register goes into the index under a kind
of its own, so "what did we actually do before the test" is searchable.

Sharing the snapshot rather than duplicating it caught one thing on the
way: the search tool's live path had to learn notes too, or fresh=true
would have quietly disagreed with the index.

305 tests; 88/89 smoke against the local instance, the one failure being
the H5P service that instance does not run. The live smoke could not be
retaken: that session has lapsed and needs a fresh jwt cookie.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

test/store.test.ts

@@ -29,11 +29,24 @@ function assertDisposable(url: string): void {
 function snapshot(
 	courses: { id: string; title: string; boardText?: string; files?: { id: string; name: string; size: number }[] }[],
 	rooms: { id: string; name: string; boardText?: string }[] = [],
+	notes: { path: string; title: string; text: string; subject?: string; date?: string }[] = [],
 ): Snapshot {
 	return {
 		crawledAt: new Date(),
 		schoolId: 'school1',
 		failures: [],
+		submissions: [],
+		lessonLog: [],
+		notes: notes.map((n) => ({
+			path: n.path,
+			title: n.title,
+			text: n.text,
+			...(n.subject ? { subject: n.subject } : {}),
+			...(n.date ? { date: n.date } : {}),
+			tags: [],
+			modifiedAt: '2026-09-15T10:00:00.000Z',
+			bytes: n.text.length,
+		})),
 		rooms: rooms.map((r) => ({
 			id: r.id,
 			name: r.name,
@@ -152,6 +165,45 @@ describe('Store', { skip: DB_URL ? false : 'set TEST_DATABASE_URL to run' }, ()
 		assert.ok(diff.changed.some((n) => n.nodeId === 'r1' && n.kind === 'room'), 'a renamed room is reported as changed');
 	});
 
+	it('indexes the user\'s own notes beside the course material', async () => {
+		// The point of the notes store: one search covers what the school
+		// uploaded and what the user wrote down in the lesson.
+		const before = await store.saveSnapshot(
+			snapshot(
+				[{ id: 'c1', title: 'Mathe', boardText: 'Prozentrechnung' }],
+				[],
+				[{ path: 'Deutsch/2026-09-15 Erörterung.md', title: 'Erörterung', subject: 'Deutsch', date: '2026-09-15', text: 'These, Argument, Fazit. Frau Meier betont den Schluss.' }],
+			),
+			'full',
+		);
+		const hits = await store.search('Erörterung', { limit: 5 });
+		const note = hits.find((hit) => hit.kind === 'note');
+		assert.ok(note, 'a note is searchable');
+		assert.equal(note.nodeId, 'Deutsch/2026-09-15 Erörterung.md', 'the path is the id get_note takes');
+		assert.equal(note.meta?.subject, 'Deutsch');
+
+		// And an edited note is a change, so what_changed reports it.
+		const after = await store.saveSnapshot(
+			snapshot(
+				[{ id: 'c1', title: 'Mathe', boardText: 'Prozentrechnung' }],
+				[],
+				[{ path: 'Deutsch/2026-09-15 Erörterung.md', title: 'Erörterung', subject: 'Deutsch', date: '2026-09-15', text: 'These, Argument, Fazit. Gegenargument nicht vergessen.' }],
+			),
+			'full',
+		);
+		const diff = await store.diff(before, after);
+		assert.ok(diff.changed.some((n) => n.kind === 'note'), 'an edited note is reported as changed');
+	});
+
+	it('keeps notes through a per-course crawl, which never looks at them', async () => {
+		// Notes belong to the account, not to a course, so a per-course refresh
+		// must carry them forward rather than appear to delete them.
+		const before = await store.latestCrawlId();
+		const after = await store.saveSnapshot(snapshot([{ id: 'c1', title: 'Mathe', boardText: 'Prozentrechnung' }]), 'c1');
+		const diff = await store.diff(before!, after);
+		assert.ok(!diff.removed.some((n) => n.kind === 'note'), 'a per-course crawl must not delete the notes');
+	});
+
 	it('carries other courses forward on a per-course crawl', async () => {
 		await store.saveSnapshot(
 			snapshot([