docs(ledger, glossary, guide): the one-namespace axis prose

The C24 axis-discovery paragraph loses its obsolete rationale (names
prefixed by the wrapping, discovery pinned to the sweep verb) in favour
of the one-raw-namespace statement; C18 records the ratified #246
bound-override coincidence contract (param_space OR bound_param_space,
no schema flag) as the document-side absorption #328 demanded; the
glossary sweep and use entries, the authoring-guide worked block, and
the README axis examples move to raw names. Refusal transcripts quote
the byte-actual binary output (review caught an invented aura: error:
prefix; the campaign-validate transcript shows the real fault_block
shape). Frozen corpora (fieldtests/, *.history.md) keep their
historical wrapped prose.

refs #328

README.md

@@ -38,7 +38,7 @@ Invoke it as `aura <command> …` (examples below use the plain name).
 - **Family** — the set of runs one verb produces over a blueprint (a sweep grid,
   a Monte-Carlo seed set, a walk-forward window sequence). Families are persisted
   in a content-addressed store and can be listed, ranked, and reproduced.
-- **Axis** — one named, sweepable knob of a blueprint (e.g. `graph.fast.length`),
+- **Axis** — one named, sweepable knob of a blueprint (e.g. `fast.length`),
   bound with a comma-separated value list. A **gang** fuses several sibling
   knobs into one axis (one value drives all members).