[Sync] Update project files from source repository (ec82cd5)

[mrz1836]

What Changed

• Removed the "Task Completion Requirements" section from .github/AGENTS.md that previously required verifying magex lint and magex test commands before task completion
• Updated goreleaser-action in .github/actions/setup-goreleaser/action.yml from v7.1.0 (commit e24998b) to v7.2.1 (commit 1a80836)
• Bumped GO_COVERAGE_VERSION from v1.3.8 to v1.3.9 in .github/env/10-coverage.env
• Bumped MAGE_X_VERSION from v1.20.15 to v1.20.16 in .github/env/10-mage-x.env

Why It Was Necessary

• Updating dependency versions ensures access to latest bug fixes, security patches, and feature improvements
• Removing the task completion requirements section streamlines agent documentation by eliminating redundant verification steps
• Keeping GitHub Actions and tooling dependencies current maintains compatibility and stability

Testing Performed

• Version bumps are routine maintenance changes with minimal risk exposure
• Updated action and tool versions will be validated through normal CI/CD pipeline execution
• Verification that workflows continue to function correctly with the updated goreleaser-action version

Impact / Risk

• Breaking Change: None - these are minor version updates and documentation changes
• Risk: Low - version bumps are incremental updates; goreleaser-action and tooling updates follow semantic versioning
• CI Impact: Minimal - workflows will use updated versions on next execution with no expected behavioral changes