Add wagmi CLI contract bridge with fork-first dev workflow

[gskril]

Summary

Sets up the contract ↔ frontend bridge using @wagmi/cli with the Foundry plugin. ABIs and deployment addresses are generated into src/generated/contracts.ts — no custom helpers, no sample contract UI.

Also expands env gitignore, adds fork-first development docs, and defaults the frontend to Anvil + Sepolia.

Changes

• wagmi.config.ts — Foundry plugin with includeBroadcasts: true (picks up addresses from contracts/broadcast/ after deploy)
• pnpm generate — runs automatically before dev and build
• .env.example + .gitignore — ignore all .env* except .env.example
• foundry.toml — RPC aliases for anvil, fork, sepolia
• src/wagmi.ts — Anvil (31337) + Sepolia, env-based RPC URLs
• docs/development.md — fork workflow, generate, env vars
• CI — frontend build job (needs Foundry for wagmi generate)

Workflow

anvil --fork-url $FORK_RPC_URL
pnpm contracts:deploy   # deploy to fork
pnpm dev                # generate + run app

Import generated exports in your own components:

import { counterAbi, counterAddress } from '@/generated/contracts'

When contracts change, re-run pnpm generate (or pnpm dev) — no wagmi config edits needed.

Test plan

• pnpm wagmi generate produces ABIs without forge-std noise
• Deploy to Anvil → regenerate → counterAddress[31337] populated
• pnpm build passes with and without broadcast data
• forge test, forge fmt --check pass