[chore] Docker socket proxy, FEVM-first defaults, CI, docs, deploy utility

[shivv23]

Description

Security hardening and developer experience improvements. All config defaults flipped to Filecoin Calibration. No contract changes.

Changes

Security

• Docker socket proxy: tecnativa/docker-socket-proxy sidecar. Canteen connects via TCP with API restricted to CONTAINERS=1, IMAGES=1. Blocks exec, volume, swarm.
• canteen/.gitignore now excludes .env and *.log
• Generated env templates no longer include private key placeholders

Configuration defaults

• config.js default chain: ethereum → filecoin
• Dashboard App.js: reads FIL_* env vars instead of ETH_*
• scheduler.js: respects DOCKER_HOST env var for socket-proxy compatibility
• dashboard .env.example defaults to filecoin

Documentation

• FEVM_CALIBRATION_SETUP.md created — full Calibration deploy guide
• SEPOLIA_SETUP.md deprecated with banner
• canteen/README.md and ARCHITECTURE.md updated to reflect Filecoin-first setup
• deploy-sepolia.sh deleted
• truffle-config.js (symlink) deleted

CI

• timeout-minutes: 10 on both jobs
• Docker compose build step added

Dashboard Dockerfile

• Multi-stage build: Node 18 → nginx

Deploy utility

• deploy-fevm.cjs: standalone deploy script for Filecoin Calibration (alternative to truffle migrate)