docs: AI SRE open public beta — remove application form and rollout gating

- Unify the AI SRE beta banner across all zh/en pages: open to all
  accounts, no application needed, free during the public beta
- Rewrite the Public Beta sections on the overview and intro pages;
  drop the subscription-tier and gradual-rollout accordions
- Update quickstart prerequisites and troubleshooting accordingly
- Rewrite the war-room AI SRE section from pre-launch future tense to
  the shipped behavior (auto diagnosis, in-chat follow-up, card context)
- Add a changelog entry announcing the open public beta

Author: ysyneu

en/ai-sre.mdx

@@ -6,7 +6,7 @@ sidebarTitle: AI SRE
 ---
 
 <Info>
-  **Public beta**: AI SRE is in public beta, rolling out gradually to accounts on On-call Pro or higher, at no additional charge during the beta. To get access, submit the [AI SRE beta application form](https://c9xudyniiq.feishu.cn/share/base/form/shrcn0ngCfdoygiaHnAT80BfZiH). Features and the UI may continue to change.
+  **Public beta**: AI SRE is now open to all accounts — no application needed. Sign in to the console and start using it; it's free during the public beta. Features and the UI may continue to evolve.
 </Info>
 
 ## What is AI SRE?
@@ -49,15 +49,11 @@ It is not a question-and-answer chatbot but a **hands-on troubleshooter**, integ
   </Card>
 </CardGroup>
 
-## Public Beta & Requirements
+## Public Beta
+
+AI SRE is now open to all accounts — no application needed. Sign in to the console and start using it.
 
 <AccordionGroup>
-  <Accordion title="Subscription requirement" icon="key">
-    AI SRE is available to accounts on **On-call Pro or higher**.
-  </Accordion>
-  <Accordion title="Gradual rollout" icon="users">
-    Access during the public beta rolls out gradually. If you don't yet see the AI SRE entry in your account, submit the [AI SRE beta application form](https://c9xudyniiq.feishu.cn/share/base/form/shrcn0ngCfdoygiaHnAT80BfZiH) and we'll enable it for you as soon as possible.
-  </Accordion>
   <Accordion title="Public beta billing" icon="gift">
     AI SRE is not billed separately during the public beta. Flashduty will share billing information ahead of general availability.
   </Accordion>

en/ai-sre/agents.mdx

@@ -6,7 +6,7 @@ sidebarTitle: Agent
 ---
 
 <Info>
-  **Public beta**: AI SRE is in public beta, rolling out gradually to accounts on On-call Pro or higher, at no additional charge during the beta. To get access, submit the [AI SRE beta application form](https://c9xudyniiq.feishu.cn/share/base/form/shrcn0ngCfdoygiaHnAT80BfZiH). Features and the UI may continue to change.
+  **Public beta**: AI SRE is now open to all accounts — no application needed. Sign in to the console and start using it; it's free during the public beta. Features and the UI may continue to evolve.
 </Info>
 
 ## Overview

en/ai-sre/apps.mdx

@@ -6,7 +6,7 @@ sidebarTitle: Apps
 ---
 
 <Info>
-  **Public beta**: AI SRE is in public beta, rolling out gradually to accounts on On-call Pro or higher, at no additional charge during the beta. To get access, submit the [AI SRE beta application form](https://c9xudyniiq.feishu.cn/share/base/form/shrcn0ngCfdoygiaHnAT80BfZiH). Features and the UI may continue to change.
+  **Public beta**: AI SRE is now open to all accounts — no application needed. Sign in to the console and start using it; it's free during the public beta. Features and the UI may continue to evolve.
 </Info>
 
 ## Overview

en/ai-sre/artifacts.mdx

@@ -6,7 +6,7 @@ sidebarTitle: Artifacts
 ---
 
 <Info>
-  **Private beta**: AI SRE is currently in private beta. Pro or higher accounts can apply for free beta access through the [AI SRE private beta application form](https://c9xudyniiq.feishu.cn/share/base/form/shrcn0ngCfdoygiaHnAT80BfZiH); after approval, Flashduty will add your account to the whitelist. Features and the UI may change during the beta.
+  **Public beta**: AI SRE is now open to all accounts — no application needed. Sign in to the console and start using it; it's free during the public beta. Features and the UI may continue to evolve.
 </Info>
 
 ## Overview

en/ai-sre/automations.mdx

@@ -6,7 +6,7 @@ sidebarTitle: Automations
 ---
 
 <Info>
-  **Public beta**: AI SRE is in public beta, rolling out gradually to accounts on On-call Pro or higher, at no additional charge during the beta. To get access, submit the [AI SRE beta application form](https://c9xudyniiq.feishu.cn/share/base/form/shrcn0ngCfdoygiaHnAT80BfZiH). Features and the UI may continue to change.
+  **Public beta**: AI SRE is now open to all accounts — no application needed. Sign in to the console and start using it; it's free during the public beta. Features and the UI may continue to evolve.
 </Info>
 
 ## Overview

en/ai-sre/environments.mdx

@@ -6,7 +6,7 @@ sidebarTitle: Environments
 ---
 
 <Info>
-  **Public beta**: AI SRE is in public beta, rolling out gradually to accounts on On-call Pro or higher, at no additional charge during the beta. To get access, submit the [AI SRE beta application form](https://c9xudyniiq.feishu.cn/share/base/form/shrcn0ngCfdoygiaHnAT80BfZiH). Features and the UI may continue to change.
+  **Public beta**: AI SRE is now open to all accounts — no application needed. Sign in to the console and start using it; it's free during the public beta. Features and the UI may continue to evolve.
 </Info>
 
 ## Overview

en/ai-sre/im.mdx

@@ -6,7 +6,7 @@ sidebarTitle: IM Platform
 ---
 
 <Info>
-  **Public beta**: AI SRE is in public beta, rolling out gradually to accounts on On-call Pro or higher, at no additional charge during the beta. To get access, submit the [AI SRE beta application form](https://c9xudyniiq.feishu.cn/share/base/form/shrcn0ngCfdoygiaHnAT80BfZiH). Features and the UI may continue to change.
+  **Public beta**: AI SRE is now open to all accounts — no application needed. Sign in to the console and start using it; it's free during the public beta. Features and the UI may continue to evolve.
 </Info>
 
 ## Overview

en/ai-sre/init.mdx

@@ -6,7 +6,7 @@ sidebarTitle: Setup
 ---
 
 <Info>
-  **Public beta**: AI SRE is in public beta, rolling out gradually to accounts on On-call Pro or higher, at no additional charge during the beta. To get access, submit the [AI SRE beta application form](https://c9xudyniiq.feishu.cn/share/base/form/shrcn0ngCfdoygiaHnAT80BfZiH). Features and the UI may continue to change.
+  **Public beta**: AI SRE is now open to all accounts — no application needed. Sign in to the console and start using it; it's free during the public beta. Features and the UI may continue to evolve.
 </Info>
 
 ## Overview

en/ai-sre/insight.mdx

@@ -6,7 +6,7 @@ sidebarTitle: Usage Insights
 ---
 
 <Info>
-  **Public beta**: AI SRE is in public beta, rolling out gradually to accounts on On-call Pro or higher, at no additional charge during the beta. To get access, submit the [AI SRE beta application form](https://c9xudyniiq.feishu.cn/share/base/form/shrcn0ngCfdoygiaHnAT80BfZiH). Features and the UI may continue to change.
+  **Public beta**: AI SRE is now open to all accounts — no application needed. Sign in to the console and start using it; it's free during the public beta. Features and the UI may continue to evolve.
 </Info>
 
 ## Overview

en/ai-sre/knowledge.mdx

@@ -6,7 +6,7 @@ sidebarTitle: Manage Knowledge
 ---
 
 <Info>
-  **Public beta**: AI SRE is in public beta, rolling out gradually to accounts on On-call Pro or higher, at no additional charge during the beta. To get access, submit the [AI SRE beta application form](https://c9xudyniiq.feishu.cn/share/base/form/shrcn0ngCfdoygiaHnAT80BfZiH). Features and the UI may continue to change.
+  **Public beta**: AI SRE is now open to all accounts — no application needed. Sign in to the console and start using it; it's free during the public beta. Features and the UI may continue to evolve.
 </Info>
 
 ## Overview