Add hands-on tutorial: CIP-30 wallet connect and first preview transaction (Mesh)

[danbaruka]

Problem

The Tutorials section currently has essentially one real hands-on guide (local-cardano-payment-detector). Newcomers who want a browser + wallet dApp path still hit a thin tutorials area (#115). The old Tools stub page was removed (#191), so we also need a clear “start building a dApp” entry that points at widely used tooling such as Mesh.

Proposed solution

Add a second tutorial that walks through:

1. Connect a CIP-30 browser wallet
2. Build a simple payment transaction with Mesh (or equivalent maintained TS SDK)
3. Sign and submit on preview testnet
4. Confirm on an explorer
5. Short troubleshooting (network mismatch, missing collateral, API keys)

Include links to Mesh docs, faucet, and DevEx Getting Started.

Acceptance criteria

• New tutorial page under website/docs/tutorials/
• Listed in Tutorials navigation / Getting Started
• Uses preview testnet (no mainnet funds required)
• Clear prerequisites and copy-pasteable steps
• npm run build succeeds

Related

• Missing content on DevEx site #115
• Too much redundant pages in Website #191 (tools stub removed; this helps replace that entry path)