chore: rename markitect_project to markitect-main across project

Finishes the in-progress rename so docs, configs, tests, and capability
manifests all reference the current repo name consistently. Fixes two
tests (test_roundtrip_consolidated.py, test_issue_140_roundtrip_simplified.py)
whose hardcoded cwd paths would have broken under the renamed directory.

Archival content under history/, reports/, and roadmap/eat-the-frog/, plus
derived artifacts (.venv_old/, node_modules/, asset_registry.json) are
intentionally left untouched.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

DEPENDENCIES.md

@@ -457,7 +457,7 @@ Sister projects can reuse these capabilities directly:
 Install capabilities via local file references:
 ```toml
 [project.dependencies]
-release-management = {path = "../markitect_project/capabilities/release-management"}
+release-management = {path = "../markitect-main/capabilities/release-management"}
 ```
 
 ### Shared Infrastructure