[plan] Implement code organization improvements from semantic analysis

[github-actions]

Overview

This tracking issue covers implementation of the refactoring recommendations identified in the semantic function clustering analysis.

Source: Issue #5506 - Semantic Function Clustering Analysis

Goals

1. Eliminate duplicate functions across the codebase
2. Consolidate small single-purpose files for better discoverability
3. Ensure consistent validation logic across packages

Planned Sub-Tasks

This work is broken down into focused, sequential tasks:

1. Consolidate extractErrorMessage() duplicate implementations - Unify two nearly identical functions with different performance characteristics
2. Unify isMCPType() validation logic - Fix critical inconsistency where different files validate different type sets
3. Consolidate prompt template files - Merge 5+ small prompt files into a single prompts.go file
4. Review parseRunURL() wrapper necessity - Assess if the CLI wrapper adds value or just indirection
5. Consolidate small utility files - Group related single-function utilities into coherent modules

Success Criteria

• ✅ Zero duplicate implementations of core functions
• ✅ Consistent validation logic across all packages
• ✅ Reduced file count through logical consolidation
• ✅ All tests passing (no functionality changes)
• ✅ Maintained or improved code discoverability

Non-Goals

• No changes to public APIs
• No new features or functionality
• No changes to validation rules (only consolidation)

Estimated Effort

Total: 11-16 hours across 5 focused tasks
Related to #5506

AI generated by Plan Command for #5506