docs: harmonize documentation and READMEs across the repo #135

Tracking issue for PR #131 (branch docs/sync-harmonize, draft).

Full documentation sync pass over 96 markdown files: 7 doc-doc contradictions arbitrated against code evidence (Vite version, Holochain client version, multi-DNA architecture, Sweettest primacy, PrivatePersonData naming, Sweettest binary count, ontology doc paths), superseded-content refresh, duplication collapsed to canonical homes.

Sequencing note: lands after PR #132 (NDO Layer 1) with a short re-sync pass over the resource-zome sections, since Layer 1 changes what these docs describe (ResourceSpecification fields, typed RuleData, OperationalState split).