fix(core): handle unsupported server error (#15164)

fix #15160
fix #15161
fix #15158
fix #15166


#### PR Dependency Tree


* **PR #15164** 👈

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 a “server version too old” message for self-hosted servers,
including the required upgrade version.
* Sign-in and OAuth-related preflight steps now verify server
compatibility before proceeding.
* **Bug Fixes**
* Improved error handling for missing/invalid server version responses
and schema/type mismatches, mapping them to the upgrade instruction.
* **Tests**
* Added coverage for server version guarding and the resulting
user-friendly error payload.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/common/error/src/index.ts

@@ -5,7 +5,8 @@ export type ErrorName =
   | keyof typeof ErrorNames
   | 'NETWORK_ERROR'
   | 'CONTENT_TOO_LARGE'
-  | 'REQUEST_ABORTED';
+  | 'REQUEST_ABORTED'
+  | 'UNSUPPORTED_SERVER_VERSION';
 
 export interface UserFriendlyErrorResponse {
   status: number;