fix: @deprecated on RequestHandlerExtra; changeset frontmatter client+server + qualifier

Author: felixweinberger

.changeset/ctx-flat-compat-getters.md

@@ -1,5 +1,6 @@
 ---
-'@modelcontextprotocol/core': patch
+'@modelcontextprotocol/client': patch
+'@modelcontextprotocol/server': patch
 ---
 
-v1-compat: add flat fields (`signal`, `requestId`, `_meta`, `authInfo`, `sendNotification`, `sendRequest`, `taskStore`, `taskId`, `taskRequestedTtl`) on the handler context (`ClientContext`/`ServerContext`) mirroring the nested `ctx.mcpReq` / `ctx.http` / `ctx.task` fields, plus the `RequestHandlerExtra` type alias. Allows v1 handler signatures to compile and run unchanged.
+v1-compat: add `@deprecated` flat fields (`signal`, `requestId`, `_meta`, `authInfo`, `sendNotification`, `sendRequest`, `taskStore`, `taskId`, `taskRequestedTtl`) on the handler context (`ClientContext`/`ServerContext`) mirroring the nested `ctx.mcpReq` / `ctx.http` / `ctx.task` fields, plus the `RequestHandlerExtra` type alias. Covers the common v1 `extra.*` accesses; HTTP-transport-specific fields (`requestInfo`, `closeSSEStream`, `closeStandaloneSSEStream`) are not shimmed and require migration to `ctx.http?.req` / `ctx.http?.closeSSE`.

packages/core/src/shared/protocol.ts

@@ -306,6 +306,8 @@ export type ServerContext = BaseContext & {
 export type ClientContext = BaseContext & LegacyContextFields;
 
 /**
+ * @deprecated Use {@linkcode ServerContext} (server side) or {@linkcode ClientContext} (client side).
+ *
  * v1 name for the handler context. v2 also exposes the same data under
  * `ctx.mcpReq` / `ctx.http`; the flat fields remain available so existing
  * handlers compile and run unchanged. See {@linkcode BaseContext}.