docs: switch author attribution from "Stephen Waits" to SWaits

Per maintainer's preference, the project's outward-facing copy now
refers to the author as [SWaits](https://swaits.com/) instead of
his legal name and email address.

Touched in this commit:
- src/00-overview.md (Status and Provenance callout)
- README.md (Provenance section + Author section; the email
  steve@waits.net is dropped — swaits.com is now the canonical
  contact)
- book.toml (authors = ["SWaits"], plain text since TOML)
- versions/v0.1.0/00-overview.md (regenerated via
  `just cut-version v0.1.0` after src/ was updated)

Git author identity on commit metadata is a separate, git/jj-config
concern and is intentionally not touched.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

versions/v0.1.0/00-overview.md

@@ -14,10 +14,10 @@
 > load-bearing.
 
 This document was primarily written by an AI (Claude, by Anthropic — mostly
-the Opus 4.x family) under the direction of Stephen Waits, with human
-proofreading and editing on top. Substantive edits — additions, audit passes,
-errata fixes — are produced through model-driven analysis of the upstream
-MeshCore C++ source and reviewed before commit.
+the Opus 4.x family) under the direction of [SWaits](https://swaits.com/),
+with human proofreading and editing on top. Substantive edits — additions,
+audit passes, errata fixes — are produced through model-driven analysis of
+the upstream MeshCore C++ source and reviewed before commit.
 
 The **upstream MeshCore C++ firmware is the source of truth** for all
 protocol behavior. This spec is downstream and derivative. Whenever the spec