refactor: move language instruction to global requirements-analysis step

Author: masamaru0513

aidlc-rules/aws-aidlc-rule-details/extensions/security/baseline/security-baseline.opt-in.md

@@ -7,8 +7,6 @@
 The following question is automatically included in the Requirements Analysis clarifying questions when this extension is loaded:
 
 ```markdown
-> Present this question in the same language as the user's conversation.
-
 ## Question: Security Extensions
 Should security extension rules be enforced for this project?
 

aidlc-rules/aws-aidlc-rule-details/extensions/testing/property-based/property-based-testing.opt-in.md

@@ -7,8 +7,6 @@
 The following question is automatically included in the Requirements Analysis clarifying questions when this extension is loaded:
 
 ```markdown
-> Present this question in the same language as the user's conversation.
-
 ## Question: Property-Based Testing Extension
 Should property-based testing (PBT) rules be enforced for this project?
 

aidlc-rules/aws-aidlc-rule-details/inception/requirements-analysis.md

@@ -92,7 +92,7 @@ Analyze whatever the user has provided:
 
 ### Step 5.1: Extension Opt-In Prompts
 
-**MANDATORY**: Scan all loaded `*.opt-in.md` files (loaded at workflow start from `extensions/` subdirectories) for an `## Opt-In Prompt` section. For each extension that declares one, include that question in the clarifying questions file created in Step 6.
+**MANDATORY**: Scan all loaded `*.opt-in.md` files (loaded at workflow start from `extensions/` subdirectories) for an `## Opt-In Prompt` section. For each extension that declares one, include that question in the clarifying questions file created in Step 6. Present each opt-in question in the same language as the user's conversation.
 
 After receiving answers:
 1. Record each extension's enablement status in `aidlc-docs/aidlc-state.md` under `## Extension Configuration`: