Upgrade golang-jwt/jwt to v5

[NitheshKG]

What type of PR is this?

bug

What this PR does / why we need it:

This PR upgrades the github.com/golang-jwt/jwt dependency to address a security vulnerability reported by Snyk.

The affected versions are vulnerable to Asymmetric Resource Consumption (Amplification) through the ParseUnverified function, where a crafted Authorization header containing excessive period (.) characters can trigger high memory allocation.

The upgrade ensures the project uses a non-vulnerable version of the JWT package and maintains compatibility with existing authentication flows.

Which issue(s) this PR fixes:

Vulnerability

Fixes #

Special notes for your reviewer:

1. Updated JWT package imports and compatibility changes required for v5 migration.
2. Executed dependency cleanup using go mod tidy.
3. Verified the project builds and existing authentication-related flows continue to work as expected.

Additional documentation e.g., usage docs, etc.:

1. Snyk vulnerability reference related to github.com/golang-jwt/jwt
2. No functional API changes introduced outside dependency migration updates.