Flagship pass establishing the crisp-prose style for the rest of
docs/: remove em dashes from explanatory prose (leave them in
simulated document/alert string literals, which are data, not our
voice), replace colon-as-dramatic-pause constructions, and fix two
broken relative links in reference/context.md ([Reasoning](reasoning)
and [Provenance](provenance) were missing their leading slash and
would 404 on the live site, the same class of bug fixed sitewide in
PR #1407). concepts.md's intro also picks up the new context/semantic
layer tagline. No code examples, tables, or technical content
changed.