feat(desktop): add monitor scheduler, Playwright CDP layer, and account health

Move monitor-task scheduling authority onto the client with a durable
file-backed queue that survives restart, drops stale cross-day tasks,
enforces per-platform serialism, and adapts global concurrency from
Electron process metrics. Publish tasks keep their existing FIFO.

Add a hidden Playwright CDP manager that attaches to Electron Chromium
on account session partitions, lets adapters opt into `executionMode:
"playwright"`, and leaves the existing hidden WebContentsView path in
place for current adapters.

Introduce an account-health subsystem with silent probes, projected
health/auth states, and IPC invalidation events so the renderer can
show accurate auth/probe status and verification timestamps.

Server-side, derive and forward title/business_date/scheduler_group_key/
question_text metadata on desktop task events so the local scheduler
can defer same-question fan-out before leasing.

apps/desktop-client/src/main/adapters/base.ts

@@ -1,5 +1,6 @@
 import type { DesktopArticleContent, JsonValue } from "@geo/shared-types";
 import type { Session, WebContentsView } from "electron";
+import type { Browser as PlaywrightBrowser, Page as PlaywrightPage } from "playwright-core";
 
 export type AdapterTaskPhase = "initial" | "resume";
 export type AdapterCompletionStatus = "succeeded" | "failed" | "unknown";
@@ -10,6 +11,10 @@ export interface AdapterContext {
   accountId: string;
   session: Session;
   view: WebContentsView | null;
+  playwright: {
+    browser: PlaywrightBrowser;
+    page: PlaywrightPage;
+  } | null;
   signal: AbortSignal;
   phase: AdapterTaskPhase;
   reportProgress(stage: string): void;