Fixes#2318. Partial follow-up to #1385 (PR-A).
Move eight historical planning documents from the root into
`docs/archive/`, keeping their original filenames and headings. Each
gets a brief archived-plan notice linking current README and deployment
guidance. Historical proposals, implementation claims and code examples
remain intact.
Validation: eight one-to-one renames, byte-preserved original content,
16 valid added links, and no inbound or executable references requiring
updates. Seven already-absent historical source paths remain plain text
under the archive notice; no replacement links were invented. All other
tracked files are unchanged.
All 218 standalone suites passed locally. The unchanged backend tree
passed full server/ingestor tests, and the unchanged app passed 12
browser smoke cases. TDD exemption: pure documentation; no test,
application, configuration or deployment change. No customizer
implications.
All eight published documents and their guidance links were verified in
Chromium. Three independent reviews passed. [CI
passed](https://github.com/Kpa-clawbot/CoreScope/actions/runs/40238488019);
its docs-only classification correctly skipped application jobs. The
full-suite results above are local validation. This only addresses PR-A;
other cleanup remains tracked separately.
