Fix the contrast and motion defects the light-base inversion left behind

[AndrewCTF]

Follow-up to the light-base inversion (bf49562). Reviewing the page against
palantir.com surfaced a set of defects that were invisible at a glance but
destroyed information, plus two that broke the page outright for some visitors.
Every number below was measured in the browser before and after.

Text that could not be read

Inverting to a light base moved --txt to near-black without re-checking the
rules that paint onto a dark surface. Six had a duplicate declaration
overriding a correct earlier one:

Element	Before	After
Six app names in the workspace grid (.tile b)	1.01:1	17.5:1
Nav section links over the hero (.nav-links a)	2.36:1	13.5:1
Focus ring, first nine tab stops (:focus-visible)	1.10:1	18.2:1
Copy button (.copy-btn)	1.79:1	7.4:1
FAQ open-state chip (details[open] .x)	1.76:1	13.6:1
Wordmark inside the open mobile menu	1:1	18.1:1

.tile b declared no colour at all, so the six app names inherited near-black
onto dark screenshots while their lighter subtitles read fine — the section is
titled "Twelve apps, one workspace" and is that claim's only evidence.
summary:hover was #fff on the white page, so hovering a FAQ question erased
it.

The blend veil was eating the product

.bleed::after had an opaque --void top stop, putting a white wash over the
first 121px of the console recording, and a 92%-black bottom stop covering
another 167px. That is 288px of 758px, and precisely the two zones the app
draws its live status bar (LINK live · FEEDS 6/6 live · CLOCK live) and its
timeline in. The chip carries its own scrim, so the gradient bought nothing.
Bands butt instead.

Scroll reveals were load-bearing

All 43 .reveal blocks started at opacity: 0 with no scripting fallback, so
a visitor with JS blocked got three background images and nothing else — the
headline, every stat, the comparison table, the FAQ and both CTAs all gone.
And because the observer unobserved on first intersection, any block the
viewport jumped over stayed invisible for good: an End-key press stranded
eleven, including a 560px band that rendered as pure white.

The hidden state is now gated on a .js class set inline, and the observer is
idempotent rather than one-shot. Verified: 0/43 stranded after jumping to the
bottom and scrolling back.

Also

• .shot had no position: relative, so its caption chip escaped to the
  initial containing block and rendered on the hero 5,000px above itself. The
  .reveal transform masked this until .in set transform: none.
• The mobile menu's only CTA was unreachable. .nav-foot was declared
  z-index: 43 then re-declared 39, and .nav-links is 42 with an opaque
  background, so elementFromPoint at the button's centre returned
  .nav-links. Keyboard could reach it; a thumb could not.
• Merged the evidence chain and the agent split into one inverted band. They
  were two sections on the same --surface tone separated by a 1px hairline,
  reading as 1,030px of a single flat empty block in the stretch of the page
  that already had the least happening. All six text roles pass AA on the new
  ground.
• Display numerals moved from Geist Mono to Archivo. Mono gives the comma a
  full monospace advance, so the headline figures read as "21 , 186".
• heroSettle now starts at exit 62%. It had the hero block at opacity 0.22
  by scrollY 700 of a 900px hero, dimming the primary CTA while it was still on
  screen and still being read.
• Hero <source> order flipped to mp4 first. That webm encode is 2.34MB
  against the mp4's 1.74MB, so order was serving every Chrome and Firefox
  visitor 34% more bytes for the heaviest asset above the fold.

Asset upload safety

website/wrangler.toml sets [assets] directory = ".", so every file beside
the page is upload-eligible — including .env, which holds a live
OPENROUTER_API_KEY. Automatic dotfile exclusion was Pages behaviour; Workers
static assets uploads whatever is in the directory. Added .assetsignore.

Deploying from a directory containing only page content is still safer, since
that list has to stay in step with whatever lands in the folder.

Verification

Deployed and checked on projectvelocity.org: all fixes present, and the
sensitive paths return 404 with an empty body — /.env, /CLIENT-NOTES.md,
/wrangler.toml, /scripts/generate-bands.mjs.

Untouched and still open: the workspace grid still uses static screenshots
rather than hover video, there is no artifact in the evidence band, and three
domain thumbnails still show imagery borrowed from other domains.