docs: update v5 announcement page (vercel#6599)

## Background

Some APIs changed and v5 site is launched.

## Summary

Updated continueUntil to stopWhen and added reference to new v5 site.

## Tasks

- [x] Formatting issues have been fixed (run `pnpm prettier-fix` in the
project root)

Author: nicoalbanese

content/docs/01-announcing-ai-sdk-5-alpha/index.mdx

@@ -8,7 +8,8 @@ description: Get started with the Alpha version of AI SDK 5.
 <Note type="warning">
   This is an early preview — AI SDK 5 is under active development. APIs may
   change without notice. Pin to specific versions as breaking changes may occur
-  even in patch releases.
+  even in patch releases. To learn more, check out the [v5
+  docs](https://v5.ai-sdk.dev)
 </Note>
 
 ## Alpha Version Guidance
@@ -34,6 +35,8 @@ During this Alpha phase, we expect to make significant, potentially breaking cha
   reliable.
 </Note>
 
+To learn more, check out the [v5 docs](https://v5.ai-sdk.dev).
+
 ## Installation
 
 To install the AI SDK 5 - Alpha, run the following command:
@@ -348,9 +351,9 @@ const result = await generateText({
 
 This makes it easier to build AI systems that adapt their capabilities based on the current context and task requirements.
 
-### continueUntil
+### `stopWhen`
 
-The `continueUntil` parameter lets you define stopping conditions for your agent. Instead of running indefinitely, you can specify exactly when the agent should terminate based on various conditions:
+The `stopWhen` parameter lets you define stopping conditions for your agent. Instead of running indefinitely, you can specify exactly when the agent should terminate based on various conditions:
 
 - Reaching a maximum number of steps
 - Calling a specific tool
@@ -360,19 +363,19 @@ The `continueUntil` parameter lets you define stopping conditions for your agent
 const result = generateText({
   // ...
   // stop loop at 5 steps
-  continueUntil: maxSteps(5),
+  stopWhen: stepCountIs(5),
 });
 
 const result = generateText({
   // ...
   // stop loop when weather tool called
-  continueUntil: hasToolCall('weather'),
+  stopWhen: hasToolCall('weather'),
 });
 
 const result = generateText({
   // ...
   // stop loop at your own custom condition
-  continueUntil: maxTotalTokens(20000),
+  stopWhen: maxTotalTokens(20000),
 });
 ```