Node 18-alpine non espone 'crypto' come global dichiarato: la libreria
@shopify/shopify-api getCryptoLib() fa 'crypto?.webcrypto' -> ReferenceError
'crypto is not defined' -> validateAppProxyHmac fallisce -> 400 su ogni richiesta
app proxy. Node 22 (come in dev) espone crypto global -> HMAC ok -> 200.
Diagnosi: log Fly mostravano 'crypto is not defined' prima di ogni 400; verificato
con firma app-proxy calcolata a mano (ora 200 + form recesso).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Mv83a29B4eFv5ixoj6PoE1