Enhance FeatureFlag type documentation and fix version references

[Copilot]

The codebase had excellent type safety patterns (LineLength, Version) but FeatureFlag lacked comprehensive documentation, and version examples in specs were outdated.

Changes

• Enhanced FeatureFlag godoc in pkg/constants/constants.go to match the comprehensive pattern used by LineLength and Version types, including example usage demonstrating type safety benefits

• Fixed outdated version references in specs/go-type-patterns.md and AGENTS.md:

  • Copilot CLI: 0.0.369 → 0.0.372
  • Claude Code: 2.0.71 → 2.0.76

Example

// FeatureFlag represents a feature flag identifier.
// This semantic type distinguishes feature flag names from arbitrary strings,
// providing type safety when working with feature toggles throughout the codebase.
//
// Example usage:
//
//     const MCPGatewayFeatureFlag FeatureFlag = "mcp-gateway"
//     func IsFeatureEnabled(flag FeatureFlag) bool { ... }
type FeatureFlag string

All semantic type aliases now have consistent, comprehensive documentation explaining their purpose and usage patterns.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• https://api.github.com/user
  • Triggering command: /usr/bin/gh gh api user --jq .login on' --ignore-path /dev/null GO111MODULE ache/go/1.25.0/x64/bin/go GOINSECURE GOMOD GOMODCACHE go env -json GO111MODULE ndor/bin/git GOINSECURE GOMOD GOMODCACHE go (http block)
  • Triggering command: /usr/bin/gh gh api user --jq .login /tmp/go-build2975489077/b373/fileutil.test -importcfg /opt/hostedtoolcache/go/1.25.0/x64/pkg/tool/linux_amd64/link -s -w -buildmode=exe /opt/hostedtoolcache/go/1.25.0/x64/pkg/tool/linux_amd64/link -o ithub/workflows -importcfg /usr/bin/git -s -w -buildmode=exe git (http block)
  • Triggering command: /usr/bin/gh gh api user --jq .login ithub/workflows -importcfg /usr/bin/git -s -w -buildmode=exe git -C 0617-22983/test-purge-invalid-1647785027 add /usr/bin/infocmp l GO111MODULE ache/go/1.25.0/x"mcp-server-playwright" --help infocmp (http block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>[plan] Document Go type safety patterns and best practices</issue_title>
<issue_description>## Objective

Create comprehensive documentation for Go type safety patterns and best practices to guide future development and prevent regression.

Context

The codebase already has excellent type safety examples (semantic type aliases in pkg/constants/constants.go, migration patterns in pkg/workflow/tools_types.go), but these patterns aren't formally documented. This issue ensures best practices are captured and easily accessible to contributors.

Approach

1. Create specs/go-type-safety.md with sections on:

   • When to use semantic type aliases (following LineLength, Version, FeatureFlag patterns)
   • When map[string]any is appropriate vs when to use structs
   • How to migrate from untyped to typed configurations
   • Examples of good and bad patterns
   • Type name collision prevention

2. Update AGENTS.md with quick reference:

   • Link to the new spec
   • Add to "Type Patterns and Best Practices" section
   • Include decision tree for choosing type patterns

3. Add inline documentation to exemplary code:

   • Add godoc comments to pkg/constants/constants.go explaining semantic types
   • Add godoc to pkg/workflow/tools_types.go explaining migration pattern
   • Document the MapToolConfig transitional pattern

4. Create a type safety checklist for PR reviews:

   • Questions to ask when reviewing new types
   • Red flags to watch for
   • When to require stronger typing

Files to Create/Modify

• Create: specs/go-type-safety.md - Comprehensive type safety guide
• Update: AGENTS.md - Add type safety quick reference
• Update: pkg/constants/constants.go - Add godoc explaining semantic types
• Update: pkg/workflow/tools_types.go - Enhance migration documentation
• Create: .github/PULL_REQUEST_TEMPLATE.md section on type safety (optional)

Acceptance Criteria

• specs/go-type-safety.md created with comprehensive guidance
• AGENTS.md updated with type safety quick reference
• Key code files have enhanced godoc comments
• Documentation includes decision trees and examples
• All examples are tested and accurate

Estimated Effort

3-4 hours
Related to #7369

AI generated by Plan Command for discussion #7368

Comments on the Issue (you are @copilot in this section)

• Fixes [plan] Document Go type safety patterns and best practices #7374

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