fix: use tenant-specific JWKS endpoint

[dhcrees]

Summary

• derive the Azure JWKS endpoint from the configured tenant id instead of always using the common endpoint
• keep a cached remote JWK set per tenant, with common as the fallback only when no tenant is supplied
• add unit tests covering tenant-specific and fallback JWKS resolution

[Copilot]

Pull request overview

Updates JWT verification in @dvsa/appdev-api-common to resolve Microsoft Azure AD JWKS endpoints per tenant, instead of always using the common endpoint, and adds unit tests for tenant-specific vs fallback behavior.

Changes:

• Derive the JWKS endpoint from the configured tenant ID (fallback to common when absent).
• Cache a createRemoteJWKSet instance per tenant to avoid rebuilding fetchers.
• Add Jest unit tests for tenant-specific and fallback JWKS resolution; bump package patch version.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
packages/appdev-common/src/auth/verify-jwt.ts	Adds tenant-derived JWKS URL selection and per-tenant caching for remote JWK sets.
packages/appdev-common/src/auth/tests/verify-jwt.spec.ts	Adds unit tests for tenant-specific vs common JWKS URL selection.
packages/appdev-common/package.json	Bumps package version to 2.0.2.

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[matthew2564]

Looks fine but you'll need to run npm i inside the package folder in order to update the lock file version