feat: add support for ed25519 tx signature verification (backport #23283)

[mergify]

Description

Closes: #1861 (for real)

This PR introduces support for ed25519 transaction signing.
The original issue was brought up in #1861, but still the support remained missing in the SDK.

It also promotes a dependency from indirect to direct (filippo.io/edwards25519), since it has handy methods for verifying ed25519 public keys.

There is logic for subtracting gas from the gas meter when an ed25519 signature is encountered, but a simple error is always returned:

cosmos-sdk/x/auth/ante/sigverify.go

Lines 537 to 540 in 80b1422

	if err := meter.Consume(params.SigVerifyCostED25519, "ante verify: ed25519"); err != nil {
	return err
	}
	return errorsmod.Wrap(sdkerrors.ErrInvalidPubKey, "ED25519 public keys are unsupported")

The change is backwards compatible, as it doesn't break existing SDK logic.

---

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Summary by CodeRabbit

Release Notes

• New Features

  • Added support for ed25519 transaction signatures, expanding transaction signing capabilities.
  • Introduced validation for ed25519 public keys to ensure they are on the correct cryptographic curve.

• Improvements

  • Simplified signature verification process by removing custom verification functions for public keys.
  • Updated signature verification process to handle ed25519 keys more efficiently.

• Documentation

  • Updated documentation to clarify the use of the tm-ed25519 scheme for both transaction authentication and consensus.

• Dependency Updates

  • Added direct dependency on filippo.io/edwards25519 package.

These changes enhance the cryptographic signature handling and provide more robust key validation in the transaction signing process.

---

This is an automatic backport of pull request #23283 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of d3e059d has failed:

On branch mergify/bp/release/v0.52.x/pr-23283
Your branch is up to date with 'origin/release/v0.52.x'.

You are currently cherry-picking commit d3e059dd2.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   crypto/keys/ed25519/ed25519.go
	modified:   crypto/keys/ed25519/ed25519_test.go
	modified:   docs/learn/beginner/03-accounts.md
	modified:   x/auth/ante/sigverify.go
	modified:   x/auth/ante/sigverify_test.go

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   CHANGELOG.md
	both modified:   go.mod

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

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[julienrbrt]

utACK