Convert medical-centre landing to React + Tailwind v4 with amoCRM lead capture

Ports the single-file MedCsFiz page — the medical centre that already runs
physiotherapy and wants the existing room to earn more — to the same
architecture as the fitness and hotel landings: Vite + React 19 + TypeScript +
Tailwind v4 on the client, Express 5 for the API, zod schema shared between the
two.

The original stays in legacy/index.html as the visual reference. Its 4 MB of
inlined CSS, JS and base64 images become 12 asset files (664 KB) plus a bundle
loaded on demand; the two 1.5 MB / 750 KB device PNGs are recompressed to webp.
The page is split into 18 components with all copy moved to src/data/content.ts.

Leads reuse the fitness amoCRM integration: contact lookup by phone in every
Russian spelling, deal in the first stage of pipeline 10980758, account fields
matched automatically with the rest written to a note. Rate limit, honeypot and
a localStorage fallback so a lead survives the CRM being down. Endpoint is
/api/leads/medical-centers-existing-physio; Vite runs on 5173 and the API on
3000.

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

medcenter/public/favicon.svg

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