Implemented XCM Payment API and updated metadata

[asiniscalchi]

PR Type

Enhancement, Tests

---

Description

• Added XcmPaymentApi implementation to support XCM payment functionalities.

• Introduced methods for querying payment assets, weight-to-fee conversion, and delivery fees.

• Updated metadata to reflect new API and associated types.

• Adjusted metadata tests to align with the new API changes.

---

Changes walkthrough 📝

	Relevant files
Enhancement	lib.rs Added `XcmPaymentApi` implementation in runtime                    runtime/laos/src/lib.rs Added XcmPaymentApi implementation for querying payment-related details. Introduced methods for acceptable payment assets, weight-to-fee conversion, and delivery fees. Imported necessary modules and updated runtime API implementation. +31/-2
Tests	metadata15.golden Updated metadata and tests for `XcmPaymentApi`                      runtime/laos/src/tests/metadata15.golden Updated metadata to include XcmPaymentApi and its methods. Added new types and adjusted existing type IDs for compatibility. Modified test outputs to align with the new API and metadata changes. +364/-36

---

Need help?

Type /help how to ... in the comments thread for any questions about PR-Agent usage.

Check out the documentation for more information.

[asiniscalchi]

/describe

[github-actions]

PR Description updated to latest commit (ffe2bcc)