Bump plutus to version 1.65.0.0

[palas]

Context

Version 1.65.0.0 of plutus includes a patch that allows cardano-wasm to compile without SRPs. So, by bumping the dependency, this PR removes one SRP, which should make maintenance easier, and no changes to the code of cardano-api were needed to compile after the bump.

How to trust this PR

The fact that it compiles without changes is a good indicator that no problems were introduced.

Checklist

• Commit sequence broadly makes sense and commits have useful messages
• New tests are added if needed and existing tests are updated. See Running tests for more details
• Self-reviewed the diff
• Changelog fragment added in .changes/

[Copilot]

Pull request overview

Updates the repository’s Plutus dependency set (via CHaP and Cabal bounds) to Plutus 1.65.0.0, with the goal of removing the WASM-specific SRP override now that upstream includes the required patch.

Changes:

• Bump plutus-core and plutus-ledger-api lower bounds to ^>=1.65 in cardano-api.cabal.
• Advance CHaP pin (flake.lock) and cabal.project index-state, and remove the WASM-only Plutus source-repository-package override.
• Add a Herald changelog fragment (note: current kind likely needs adjustment per review comment).

Reviewed changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated 1 comment.

File	Description
flake.lock	Updates the locked CHaP revision/hash to pick up Plutus 1.65.0.0.
cardano-api/cardano-api.cabal	Raises plutus-core / plutus-ledger-api bounds in library + golden tests.
cabal.project	Updates CHaP index-state and removes WASM-only Plutus SRP override.
.changes/20260525_211121_cardano-api_pablo.lamela_update_plutus.yml	Adds changelog fragment (currently marked maintenance).