feat: reorganize workflows with prefix-based naming and merge duplicates

✨ Major reorganization of workflow files and documentation

📝 Prefix Categories Applied:
  • terraform- → tf- (9 workflows)
  • cloudformation- → cf- (3 workflows)
  • pr- prefix for PR-related workflows (auto-assignee, auto-merge, checks, lock, stale, etc.)
  • aws- prefix for AWS-specific workflows
  • gcp- prefix for GCP-specific workflows
  • release- prefix for release workflows
  • notify- prefix for notification workflows
  • security- prefix for security scanning workflows
  • yl- prefix for YAML lint workflows (ymllint → yl-lint)

🔄 Merged Duplicate Workflows:
  • Merged tf-checks.yml + tf-tf-checks.yml → tf-checks.yml (with optional version checking)
  • Merged tf-workflow.yml + tf-workflow-target.yml → tf-workflow.yml (with optional targeting)

📚 Documentation Updates:
  • Removed numbered prefixes from all documentation files
  • Updated all workflow references in documentation
  • Reorganized README.md alphabetically by prefix category
  • Updated all file paths and examples

🎯 Files Renamed:
  • 40 workflow files renamed with consistent prefixes
  • 32 documentation files renamed and organized
  • All references updated throughout repository

✅ Benefits:
  • Consistent naming convention across all workflows
  • Easier to find workflows by category
  • Shorter, more readable file names
  • Better organization and maintainability

Author: anmolnagpal