Chore/opa leftovers

[rmlearney-digicatapult]

Pull Request

Checklist

• Have you read Digital Catapult's Code of Conduct?
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• I have added tests that prove my fix is effective or that my feature works.
• New and existing unit tests pass locally with my changes.

PR Type

Please delete options that are irrelevant.

• Chore

Linked tickets

High level description

Remove remaining OPA leftovers after 2024 extraction

Detailed description

Cleaned up remaining OPA mentions/type

Describe alternatives you've considered

Operational impact

Additional context

[Copilot]

Pull request overview

Removes remaining Open Policy Agent (OPA) artifacts and references after the 2024 extraction, plus a patch version bump to reflect the cleanup.

Changes:

• Removed opaOrigin from ServerConfig and deleted an unused OPA rego policy file.
• Updated internal Copilot/repo instructions to reflect current Docker Compose setup (no OPA).
• Bumped package version to 0.19.2.

Reviewed changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/utils/ServerConfig.ts	Removes leftover OPA-related config surface (opaOrigin).
package.json	Bumps package version to 0.19.2.
package-lock.json	Bumps lockfile version header (but currently leaves an internal version mismatch that needs fixing).
docker/opa/suppliers.rego	Deletes OPA rego policy file.
.github/copilot-instructions.md	Updates docs to remove OPA compose references and reflect current compose topology.