fix(ci): add explicit permissions to docker jobs to fix ghcr push failure

[Harshita264]

Closes #256

What This PR Does

Adds explicit permissions blocks to the build-and-test-docker and security-scan jobs in .github/workflows/ci.yml to fix the GHCR push failure.

Root Cause

The workflow had a top-level permissions block with packages: write, but GitHub Actions does not reliably propagate top-level permissions to individual jobs when using fine-grained tokens or GitHub App installations. The build-and-test-docker job was attempting to push to ghcr.io/nitya-003/innerhue:main without an explicit packages: write grant at the job level, causing:

Changes Made

Added explicit permissions block to two jobs in ci.yml:

build-and-test-docker

permissions:
  contents: read
  packages: write

security-scan

permissions:
  contents: read
  packages: write

The top-level permissions block, docker/login-action registry config, and GITHUB_TOKEN usage were already correct — no other changes were needed.

Testing

This fix can be verified by merging to main and observing the build-and-test-docker job successfully push toghcr.io/nitya-003/innerhue:main without the denied error.

Why This Matters

The Docker publish pipeline has been broken since the workflow was introduced. Without this fix, no Docker images are ever pushed to GHCR, making the entire CI/CD publish pipeline non-functional.

[vercel]

@Harshita264 is attempting to deploy a commit to the Nitya Gosain's projects Team on Vercel.

A member of the Team first needs to authorize it.