Convert fitness landing to React + Tailwind v4 with amoCRM lead capture

Port the single-file landing (2.6 MB of inlined CSS, JS and base64 images,
kept as fitnes/legacy/index.html) to Vite + React 19 + TypeScript, with an
Express API that files every form submission into amoCRM pipeline 10980758.

- Extract the 14 embedded images to src/assets/images and public/
- Rebuild the design system as Tailwind v4 @theme tokens; the stock palette and
  breakpoints are cleared so only the EXO scale is reachable from utilities
- Split the page into 15 components; all copy moves to src/data
- Lead endpoint: find-or-create the contact (Russian phone spellings compared on
  the last 10 digits), create the lead in the pipeline's first stage, map the
  fields the account already has and put the rest in a note. If amoCRM is
  unreachable the payload is logged and kept in localStorage rather than lost.
- Add a callback modal as a second entry point, tagged separately in the pipeline
- Self-host Inter Variable so the layout's 760/850/900 weights render as real
  weights instead of snapping to bold

Fidelity was checked by comparing section offsets and heights against the
original at 375/480/640/900/1120/1440 px; every section and the total page
height matched exactly. Loading Inter deliberately changes text metrics, so the
byte-exact comparison holds against the pre-font build.

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

fitnes/public/favicon.svg

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