feat(#207): remove legacy coverage-bucket and dist-requiring tests

- Removed pre-migration broad coverage-bucket suites and their reference copies
- Removed dist-requiring integration and guardrail tests as mirrored suites cover the same behavior
- Updated test-loading guidance to follow a source-mirrored, dot-source-first pattern
- Finalized Pester coverage target at 99% with migrated test suite
- Enhanced architect/design flow for finalization processes

Author: stiwicourage

CHANGELOG.md

@@ -32,9 +32,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 
 
 ### Changed
-- Retired the pre-migration broad coverage-bucket suites (`CoverageGaps*`, `CoverageCompletion*`, `Remaining*Coverage*`, broad `NovaCommandModel*`) by moving them to `tests/_legacy/` and renaming the `.Tests.ps1` suffix to `.LegacyReference.ps1` so Pester discovery no longer runs them. The mirrored `tests/public/` and `tests/private/<domain>/` suites added in #200 – #206 now own that coverage; the retired files stay readable as a reference until coverage measurement is re-enabled and confirms no regression.
+- Removed the pre-migration broad coverage-bucket suites (`CoverageGaps*`, `CoverageCompletion*`, `Remaining*Coverage*`, broad `NovaCommandModel*`). The mirrored `tests/public/` and `tests/private/<domain>/` suites added in #200 – #206 now own that coverage, and the restored 99% measured coverage confirms no regression, so the parked `tests/_legacy/` reference copies are no longer needed.
 - Migrated the remaining mirrored private-helper tests (`tests/private/update/`, `tests/private/quality/`, `tests/private/build/InvokeNovaBuildWorkflow.Tests.ps1`, and `tests/private/scaffold/`) off the legacy `Import-Module dist + InModuleScope` pattern to the dot-source-first model, so the full mirrored test suite runs against `src/**/*.ps1` directly and does not require a prior `Invoke-NovaBuild`.
-- Retired the dist-requiring integration and guardrail tests (`Module`, `OutputFiles`, `BuildOptions`, `CiCoverage`, `CliHelperCoverage`, `CliSharedParser`, `PackageLatestPolicy`, `PreambleBuild`, `UpdateNotification`) by moving them to `tests/_legacy/` with the `.LegacyReference.ps1` suffix and moving their `*TestSupport.ps1` sidecars alongside them, so `nova test` no longer depends on `dist/NovaModuleTools` being built first. Their behavior is now covered by the mirrored suites for each touched helper.
+- Removed the dist-requiring integration and guardrail tests (`Module`, `OutputFiles`, `BuildOptions`, `CiCoverage`, `CliHelperCoverage`, `CliSharedParser`, `PackageLatestPolicy`, `PreambleBuild`, `UpdateNotification`) and their `*TestSupport.ps1` sidecars now that the mirrored suites cover the same behavior and `nova test` no longer depends on `dist/NovaModuleTools` being built first.
 - Test-loading guidance for NovaModuleTools' own tests and for generated Agentic Copilot scaffolds now follows a source-mirrored, dot-source-first pattern: new mirrored tests dot-source the relevant `src/**/*.ps1` files directly in `BeforeAll` instead of importing the built `dist` module or wrapping assertions in `InModuleScope`, so tests run against source files and JaCoCo coverage references real source paths.
 - `project.json` `Pester.CodeCoverage.Enabled` is `true` with a `99` percent target that the migrated, source-mirrored test suite now satisfies; this finalizes the temporary disable from the test-layout migration.
 - The architect/design flow now surfaces settled vs unresolved design items before finalization, offers explicit choices for full finalization vs design-package-only handoff, clarifies how to use design notes versus the paste-ready GitHub issue draft, and requires finalization output to follow the project Markdown authoring guidance.