fix bee chain config — use BEE_BLOCKCHAIN_RPC_ENDPOINT

Bee 2.x renamed BEE_SWAP_ENDPOINT to BEE_BLOCKCHAIN_RPC_ENDPOINT. With
the old name, Bee silently disables the chain backend and shuts down
with `factory fail: chain disabled`. Wire the endpoint inline so it
doesn't depend on the host .env.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

hostinger/.env.example

@@ -26,7 +26,6 @@ BEE_STAMP_TTL_DAYS=30
 
 # Used by the Bee service itself (BEE_*_PASSWORD vars below):
 BEE_PASSWORD=change-me
-BEE_SWAP_ENDPOINT=https://rpc.gnosischain.com
 
 # --- Pricing ---
 MARKUP_BPS=2000