Update README: add ERC author checklist to reduce review overhead

[arawrdn]

Hi,

Add the checklist near “Before you write an ERC”. Looks good as a docs-only refactor: it consolidates existing requirements and should cut repeat editor nit comments.

Suggested wording with a small tweak for precision:

## ERC Author Checklist

Before opening a pull request, confirm that:

- The idea has been discussed on Ethereum Magicians or Ethereum Research.
- The proposal follows the structure and requirements in EIP-1.
- The ERC targets the Ethereum application layer, not consensus-layer, networking, or interface-level changes.
- The preamble includes a valid `discussions-to` link.
- The document is written as a standard, not as an implementation support request.
- Once published at `https://eips.ethereum.org/`, the ERC uses the canonical citation format.

Why the tweak:

• consensus-layer is clearer than just consensus.
• not as an implementation support request reads cleaner.
• The citation bullet avoids implying the draft must already have a published URL before opening the PR.

Good placement:

## Before you write an ERC

...

## ERC Author Checklist

...

This keeps the checklist close to the author onboarding flow without changing process rules.

Cheers,

[eip-review-bot]

File README.md

Requires 2 more reviewers from @g11tech, @jochem-brouwer, @lightclient, @samwilsn, @xinbenlv

[github-actions]

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