Write 'Interact with Your Contract' (evm/quickstart/interact-with-contract)

**Page:** `evm/quickstart/interact-with-contract.mdx`

**Scope:** After deploying, read from and write to a contract via ethers/viem + JSON-RPC. Follows the `deploy-with-*` pages.

### Acceptance criteria
- [ ] Replace the placeholder template with real content
- [ ] Remove `hidden: true` from the frontmatter
- [ ] Follow the style guide: **markdown tables only** (no HTML ``), and avoid AI-tell phrasing (no em-dashes, "delve", "leverage", "not just X but Y")
- [ ] Add working cross-links to related pages
- [ ] Confirm any code samples run on testnet