feat(editor): the simulation's properties in a sheet of their own, with a restart for everyone

Who started the simulation, "Pakete verwerfen" and the dropped packets move
from the toolbar into a properties sheet beside the surface. New in it: restart
the simulation, after asking. The room learns a restart message: stopped as by
stop, every capture, dropped frame and program window emptied, started anew
and named after who restarted; refused for readers and frozen projects, logged,
and waiting for asked blobs like a start.

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

packages/server/test/blobs.test.ts

@@ -222,12 +222,15 @@ describe('the blobs on F', () => {
     expect(BLOB_ASKS).toBe(5);
   }, 30_000);
 
-  it("starts a simulation only once the blobs asked for have come, however slow F's store is", async () => {
-    const { project, notebook, bytes } = await projectWithPicture(51);
+  it.each([
+    ['start', 51],
+    ['restart', 52],
+  ] as const)("starts a simulation (%s) only once the blobs asked for have come, however slow F's store is", async (kind, seed) => {
+    const { project, notebook, bytes } = await projectWithPicture(seed);
     await blobs.put(bytes);
     const server = await startTestServer(store, sessions, { blobs: slowly(blobs, { get: 800 }) });
     const room = await enterRoom(server, project);
-    room.send({ kind: 'start' });
+    room.send({ kind });
     await until(() => room.got.some((message) => message.kind === 'state' && message.mode === 'simulation'), 5_000);
     room.send({ kind: 'input', node: notebook, app: 'terminal', action: 'enter', args: { line: 'cp spaet.png kopie.png' }, reqId: 'r' });
     await until(() => room.got.some((message) => message.kind === 'ack'));