test(desktop): cover deepseek account name extraction for wechat + phone logins

Refactor readDeepseekAccountIdentity so the JSON payload parser is a pure
ts function (extractDeepseekIdentityFromPayload). The webContents IIFE now
just polls for userToken and returns the raw API JSON; payload picking lives
in ts and is unit-tested.

Tests lock the contract for both login types we observed in the wild:
  - WeChat-bound account: id_profile.name = '阿白', picture present.
  - Phone-only login: id_profile = null, mobile_number = '177******08',
    email = '' (empty string, not null) — the case that originally regressed.

Plus regressions for the priority order (profile.name > mobile_number > email),
the all-empty fallback, and non-record payloads.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/shared-types/src/index.ts

@@ -1352,6 +1352,7 @@ export interface MonitoringDashboardRuntime {
   platform_authorization_status: MonitoringPlatformAuthorizationStatus
   authorized_monitoring_platform_ids: string[]
   authorized_monitoring_platform_count: number
+  online_authorized_monitoring_platform_ids?: string[]
 }
 
 export interface MonitoringDashboardCompositeResponse {