Harness docs

Source: docs/README.md
Status: current

Public product docs only. Pick a persona; follow one path.

Persona	Path
Canon / ontology	`canon/` — grain, proposals, standard toolkit
Runtime implementer	`runtime/` · `decisions/`
Plugin author	`plugins/`
Shell author	`client/shell.md`
Operator	`client/operate.md`
Tape / watch	`client/transcript.md`

Package map and product one-liner: ../README.md.