perf(scenario-scheduler): parallelize stale-run cleanup on startup with effect

- use Effect.forEach with concurrency:10 to fail up to 10 runs in parallel
- isolate each failRun with catchAll so one failure doesn't abort the rest
- log unexpected failRun errors per run without halting the batch

server/package.json

@@ -32,6 +32,7 @@
     "better-sqlite3": "^12.8.0",
     "class-transformer": "^0.5.1",
     "class-validator": "^0.14.4",
+    "effect": "^3.21.0",
     "jsdom": "^29.0.2",
     "playwright": "^1.59.1",
     "reflect-metadata": "^0.2.2",

server/src/scenario/scenario-scheduler.service.ts

@@ -2,6 +2,7 @@ import { Injectable, OnModuleInit } from "@nestjs/common";
 import { Interval } from "@nestjs/schedule";
 import { InjectRepository } from "@nestjs/typeorm";
 import * as crypto from "crypto";
+import { Effect } from "effect";
 import type { Browser, BrowserContext, Page } from "playwright";
 import { chromium } from "playwright";
 import { Repository } from "typeorm";
@@ -76,11 +77,29 @@ export class ScenarioSchedulerService implements OnModuleInit {
       this.logger.error(
         `Run #${run.id}: marked fail due to server restart (playwright session lost)`,
       );
-      await this.failRun(
-        run.id,
-        "Run aborted: server restarted and playwright session could not be recovered",
-      );
     }
+
+    await Effect.runPromise(
+      Effect.forEach(
+        staleRuns,
+        (run) =>
+          Effect.tryPromise(() =>
+            this.failRun(
+              run.id,
+              "Run aborted: server restarted and playwright session could not be recovered",
+            ),
+          ).pipe(
+            Effect.catchAll((err) =>
+              Effect.sync(() =>
+                this.logger.error(
+                  `Run #${run.id}: failRun threw unexpectedly — ${String(err)}`,
+                ),
+              ),
+            ),
+          ),
+        { concurrency: 10 },
+      ),
+    );
   }
 
   /**