rename(547): what people read says Grimoire

Step 1 of the Scribe -> Grimoire rename: every capitalised "Scribe" in prose
becomes "Grimoire" ("Fabled Scribe" -> "Fabled Grimoire") across the UI,
the PWA manifest and page title, the MCP instructions and tool docstrings,
hook and skill text, docs and README, with the tests that assert on that
prose moving with it. Old migrations keep their wording.

Identifiers are untouched here: the package, plugin name, MCP server key,
hook file names, env vars, the .scribe marker and FabledScribe repo/image
names move in steps 2 and 3, along with prose that quotes them.

The sweep matched "Scribe" only as a whole word, so describe/subscribe and
friends are untouched. The longer name took the MCP instructions one
character over their 1,600 budget; two phrases are shortened to fit.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

ci-requirements.md

@@ -29,7 +29,7 @@ Anything CI installs at job time that isn't in the image. Promotion
 candidates if more than one project needs them.
 
 - `shellcheck` — apt-installed in the **plugin** job, which lints the
-  Claude Code hook scripts and runs their fail-open smoke test. Scribe is
+  Claude Code hook scripts and runs their fail-open smoke test. Grimoire is
   its only consumer, so per `docs/process.md` it stays per-job. It is small
   (~20 MB) and a promotion candidate once another project lints shell.