fix(docs-check): allow ADRs under docs/decision-records/template/

[NWarila]

Summary

tools/check_docs_layout.py was not updated when PR #44 introduced the template-tier ADR. The framework's own CI workflow only runs terraform fmt/init/validate/test, so this never failed framework-side, but consumers (github-terraform-runner) that run make ci against this framework as part of contract validation surface the layout error.

Aligns with the convention in all four template repos which already include 'template' in ADR_ALLOWED_SUBTREES.

Test plan

• CI green

[github-actions]

Terraform Framework Test Results

Check	Status
Format	✅
Init	✅
Validate	✅
Test Suite	✅

Runs: 55 total, 55 passed, 0 failed, 0 skipped

Full test output

tests/normalization.tftest.hcl... in progress
  run "pattern_blocks_with_only_pattern_field_plans_clean"... pass
  run "merge_queue_with_partial_fields_plans_clean"... pass
  run "pull_request_with_only_merge_methods_plans_clean"... pass
  run "pages_partial_fields_plans_clean"... pass
  run "repo_with_environments_plans_clean"... pass
  run "archived_repo_plans_clean"... pass
  run "empty_repo_set_plans_clean"... pass
  run "org_mode_explicit_codeowners_plans_clean"... pass
  run "personal_mode_synthesizes_codeowners"... pass
  run "push_ruleset_on_private_when_supported_plans_clean"... pass
  run "license_template_defaults_null_not_MIT"... pass
  run "good_minimal_produces_expected_resource_counts"... pass
  run "good_minimal_carries_expected_defaults"... pass
  run "archived_repo_filters_out_downstream_locals"... pass
  run "empty_repo_set_exercises_every_filter_on_zero_input"... pass
  run "good_minimal_produces_zero_environments_zero_codeowners"... pass
  run "explicit_security_and_analysis_overrides_baseline"... pass
  run "multi_branch_sources_all_from_default_not_serially"... pass
  run "fork_repo_passes_through_source_fields"... pass
tests/normalization.tftest.hcl... tearing down
tests/normalization.tftest.hcl... pass
tests/preconditions.tftest.hcl... in progress
  run "rejects_invalid_visibility_enum"... pass
  run "rejects_public_repo_without_description"... pass
  run "rejects_invalid_ruleset_enforcement"... pass
  run "rejects_org_mode_codeowners_required_but_missing"... pass
  run "rejects_env_wait_timer_out_of_range"... pass
  run "rejects_env_branch_policy_mutually_exclusive"... pass
  run "rejects_actions_allowed_actions_enum"... pass
  run "rejects_actions_selected_without_config"... pass
tests/preconditions.tftest.hcl... tearing down
tests/preconditions.tftest.hcl... pass
tests/security.tftest.hcl... in progress
  run "strict_mode_no_gap_plans_clean"... pass
  run "compatibility_mode_no_gap_plans_clean_with_empty_preview"... pass
  run "strict_mode_reports_gaps_across_multiple_visibilities"... pass
  run "no_baseline_no_yaml_collapses_security_to_null"... pass
  run "baseline_feature_enabled_when_capability_matches"... pass
tests/security.tftest.hcl... tearing down
tests/security.tftest.hcl... pass
tests/validation.tftest.hcl... in progress
  run "good_minimal_plans_clean"... pass
  run "rejects_unknown_top_level_key"... pass
  run "rejects_unknown_nested_key"... pass
  run "rejects_allow_forking"... pass
  run "rejects_duplicate_repo_keys"... pass
  run "rejects_unsupported_push_ruleset"... pass
  run "rejects_code_scanning_tool_typo"... pass
  run "rejects_multiple_nested_typos_in_one_repo"... pass
  run "rejects_secrets_written_as_map"... pass
  run "rejects_token_mode_missing_token"... pass
  run "rejects_app_mode_missing_app_auth"... pass
  run "rejects_token_mode_with_app_auth_also_set"... pass
  run "rejects_app_mode_with_token_also_set"... pass
  run "valid_app_auth_plans_clean"... pass
  run "strict_mode_fails_on_capability_gap"... pass
  run "compatibility_mode_tolerates_capability_gap"... pass
  run "push_ruleset_public_supports_true_still_fails"... pass
  run "push_ruleset_private_supports_false_fails"... pass
  run "push_ruleset_internal_supports_true_passes"... pass
  run "push_ruleset_internal_supports_false_fails"... pass
  run "rejects_invalid_github_owner_regex"... pass
  run "rejects_invalid_auth_mode_enum"... pass
  run "rejects_invalid_baseline_mode_enum"... pass
tests/validation.tftest.hcl... tearing down
tests/validation.tftest.hcl... pass

Success! 55 passed, 0 failed.

Commit: f7c088c