feat(core): improve login flow (#15219)

#### PR Dependency Tree


* **PR #15219** 👈

This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **New Features**
* Added secure, automatic auth session token refresh and request replay
for expired-token responses across Android, iOS, and Electron.
* Updated sign-in flows to manage sessions without returning tokens to
the app layer.
* Added “Devices” management UI with sign out per device and sign out
all.
  * Enabled support for both Hashcash and Turnstile captcha providers.
* **Bug Fixes**
* Improved refresh de-duplication, inflight cancellation/clear behavior,
and recovery from corrupted/invalid sessions.
* **Tests**
* Expanded auth-session, refresh/revoke, and replay coverage (Electron
unit tests, Android instrumentation tests, iOS auth date parser tests).
* **Chores**
* Removed CAPTCHA site key from build-time configuration and adjusted CI
test execution.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

tools/@types/build-config/__all.d.ts

@@ -36,7 +36,6 @@ declare interface BUILD_CONFIG_TYPE {
   linkPreviewUrl: string;
 
   SENTRY_DSN: string;
-  CAPTCHA_SITE_KEY: string;
 }
 
 declare var BUILD_CONFIG: BUILD_CONFIG_TYPE;