Remove duplicated AI-attribution lines from Code Simplifier and Repository Quality Improver templates (#354)

* Initial plan

* Remove duplicate hard-coded attribution lines in workflow templates

Co-authored-by: dsyme <7204669+dsyme@users.noreply.github.com>

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: dsyme <7204669+dsyme@users.noreply.github.com>
Co-authored-by: Peli de Halleux <pelikhan@users.noreply.github.com>

Author: 3 people

workflows/code-simplifier.md

@@ -269,8 +269,6 @@ Please verify:
 - No unintended side effects
 
 ---
-
-*Automated by Code Simplifier Agent*
 ```
 
 ### 4.3 Use Safe Outputs

workflows/repository-quality-improver.md

@@ -357,8 +357,6 @@ The following actionable tasks address the findings above.
 1. [Action 1] — Priority: Medium
 
 ---
-
-*Generated by Repository Quality Improvement Agent*
 *Next analysis: [Tomorrow's date] — Focus area selected based on diversity algorithm*
 ```