T9.3 - S6: one icon system - monochrome text glyphs, one meaning each

The set mixed colour emoji with dingbats, and the same glyph read as two
things partly BECAUSE emoji render as per-platform artwork. The system chosen:
monochrome text-presentation glyphs - the suite is classic-script vanilla HTML
with no bundler, so an SVG sprite or icon font is a new asset pipeline, while
text glyphs render through the same font stack as the words beside them. The
enforceable form of "renders identically on Windows, macOS and a tablet":
no emoji-range codepoint and no U+FE0F selector anywhere in UI source,
swept by the probe on every run.

Converted: green-check/red-cross emoji in the admin and users consoles to
checkmark/cross, no-entry to circled-slash (blocked/on hold), the lock to the
pencil already meaning "edit with a logged reason" on sign-offs, the star to
the diamond, the folder to the reference marker, the side nav's lightning to
the gear, and the WATCH glyph (U+231A - emoji-presentation BY DEFAULT per
Unicode) to a text-presentation clock face. Dropped where the label already
carried the meaning: lightning on Save & view, the camera on Add photo, the
page/frame pictograms on file rows (the filename is the label). Stale help
copy fixed while its emoji left: it still described the pre-T9.4 "Load
sample" and the pre-T7.10 "Usage Logs" locations.

The meaning-to-icon mapping is in docs/reference/tokens.md - one meaning per
glyph, one glyph per meaning, both directions asserted from the document
itself; the probe also sweeps every page for glyphs not in the approved set,
so an unmapped icon cannot creep in.

Verification (each probe run alone): NEW tests/icon_check.py 5/5.
Regressions: frame_check 38/38, files_check 36/36, a11y_check 22/22,
cards_check 44/44.

Items: S6

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docs/reference/file-map.md

@@ -301,6 +301,7 @@ Wave 9 adds these:
 ```bash
 python tests/export_check.py         # CR-008/CR-017 - export walk + hours guard   20 checks
 python tests/sample_check.py         # S7 - one sample affordance, confirmed+fenced 10 checks
+python tests/icon_check.py           # S6 - one icon system, no emoji, mapped        5 checks
 ```
 
 **Three probes were re-pointed at `T7.1`.** `sections_check.py` 5b drove the live