Expose submissions: list_submissions, and get_task shows your own

Adds what the API actually permits, which is less than the request asked
for and worth being precise about.

GET /api/v3/submissions/status/task/{taskId} is the only submission
route — no list, no fetch-by-id — so a task id is the only way in. The
probe in the report missed it by trying /api/v3/submissions (404). Its
payload is {id, submitters, isSubmitted, isGraded, grade,
submittingCourseGroupName} and nothing more: no submitted text, no grade
comment, no graded-at. Those lived on /api/v1, which this instance does
not serve at all (404 across the board, confirmed — not the proxy). So
"what feedback did I get" is answerable only when the feedback is a file.

Submitted files are reachable, which covers the main workflow:
get_task now shows the submission id, graded state, grade, group, and
the handed-in files with ids ready for download_file. list_submissions
surveys tasks for "what have I handed in" and "what is still ungraded".
Both state the text/feedback gap rather than implying none was given.

Two things found while building it:

files-storage ignores the parentType path segment when listing —
.../gradings/{id} returns the same records, saying parentType
"submissions". Filtering on each record's own parentType, or a student's
own upload gets reported back as teacher feedback.

get_task could not find this task at all: the task lists only cover the
dashboard, and group-project tasks are absent from both, so it claimed
the id was wrong for a task the account can plainly see. It now falls
back to scanning course pages.

Also bounds live search by measured cost: resolving attachments needs a
request per board element, which is 2s for one course but 325s for all
of them — beyond any client timeout. An unscoped fresh search now reads
text only and says so.

38/38 smoke checks; verified end to end through Claude Code against a
real graded group submission.

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

src/core/client.ts

@@ -12,6 +12,7 @@ import type {
 	MeResponse,
 	NewsResponse,
 	Paginated,
+	SubmissionStatus,
 	TaskContent,
 } from './types.ts';
 
@@ -281,6 +282,22 @@ export class SchulcloudClient {
 		});
 	}
 
+	// --- submissions -----------------------------------------------------
+
+	/**
+	 * Submission statuses for one task.
+	 *
+	 * The only way to obtain a submission id: there is no `GET /submissions` and
+	 * no `GET /submissions/{id}`. What comes back depends on the account — a
+	 * student sees their own submission, a teacher sees the whole class's.
+	 */
+	async listSubmissionStatuses(taskId: string): Promise<SubmissionStatus[]> {
+		const page = await this.getJson<{ data: SubmissionStatus[] }>(
+			`/api/v3/submissions/status/task/${encodeURIComponent(taskId)}`,
+		);
+		return page.data ?? [];
+	}
+
 	// --- lessons ---------------------------------------------------------
 
 	getLesson(lessonId: string): Promise<LessonResponse> {

src/core/types.ts

@@ -218,6 +218,26 @@ export const FILE_PARENT_TYPES: FileParentType[] = [
 	'externaltools',
 ];
 
+/**
+ * One submission's status for a task.
+ *
+ * This is the entire submission surface the v3 API offers — there is no
+ * endpoint for the submitted *text*, the grade comment, or a graded-at
+ * timestamp, and the legacy `/api/v1` surface that once carried them is not
+ * served on this instance (404, not proxied away). Submitted work that is a
+ * file is still reachable, through files-storage.
+ */
+export interface SubmissionStatus {
+	id: string;
+	/** User ids. A group submission lists every member. */
+	submitters: string[];
+	isSubmitted: boolean;
+	isGraded: boolean;
+	/** Present only when a numeric grade was given; often null even if graded. */
+	grade?: number | null;
+	submittingCourseGroupName?: string;
+}
+
 export interface DashboardResponse {
 	id: string;
 	gridElements: {