test: remove the retired reactive process fixture

tests/fixtures/processReactiveScenario.mjs

@@ -1,36 +0,0 @@
-import { spawn, spawnSync } from "node:child_process";
-import { writeFile } from "node:fs/promises";
-
-import { WebSocket } from "ws";
-
-process.stdout.write("Ready\n");
-const worker = spawn(
-  process.execPath,
-  ["-e", 'process.title = "rea-reactive-worker"; setTimeout(() => {}, 750);'],
-  { stdio: "ignore" },
-);
-// "Collecting" must reach the capture coordinator as an observation *after*
-// the one carrying "Ready", because the ready transition consumes that
-// observation and advances the terminal frontier. Writing both back to back
-// let the PTY coalesce them into a single chunk, so whether the collecting
-// trigger could match depended on host timing and the multi-source run
-// intermittently resolved target_lost instead of passed. The synchronous probe
-// below guarantees the reader has drained the first chunk before this one.
-spawnSync(process.argv[2], ["probe"], { stdio: "ignore" });
-process.stdout.write("Collecting\n");
-await writeFile("reactive-result.txt", "created");
-await fetch(`${process.env.REA_REPLAY_HTTP_URL}/reactive`);
-await new Promise((resolve, reject) => {
-  const socket = new WebSocket(process.env.REA_REPLAY_WEBSOCKET_URL);
-  socket.once("open", () => socket.send("reactive-client"));
-  socket.once("message", () => socket.close());
-  socket.once("close", resolve);
-  socket.once("error", reject);
-});
-await new Promise((resolve, reject) => {
-  worker.once("exit", resolve);
-  worker.once("error", reject);
-});
-// Let the parent capture coordinator ingest final protocol and filesystem events
-// before the root process exits and submits its terminal loss signal.
-await new Promise((resolve) => setTimeout(resolve, 25));