Move away from gitpkg.now.sh

[brionmario]

Purpose

This pull request updates the way the @wso2/eslint-plugin and @wso2/prettier-config development dependencies are referenced across multiple package.json files. Instead of using the previous gitpkg.now.sh URLs, the dependencies now point directly to specific commits in the GitHub repository using the git+https format, which is a more standard and reliable method for installing packages from GitHub.

Dependency source updates:

• Updated @wso2/eslint-plugin and @wso2/prettier-config in the root package.json to use the git+https://github.com/... syntax with a specific commit hash and path, replacing the old gitpkg.now.sh URLs.
• Made the same update for these dependencies in examples/express-vetassist-mcp-server/package.json.
• Applied the update in packages/mcp-express/package.json as well.
• Updated the dependency references in packages/mcp-node/package.json to match the new format.

Related Issues

• N/A

Related PRs

• N/A

Checklist

• Manual test round performed and verified.
• Documentation provided.
• Unit tests provided.

Security checks

• Followed secure coding standards in http://wso2.com/technical-reports/wso2-secure-engineering-guidelines
• Ran ESLint and Prettier fixed any issues.
• Confirmed that this PR doesn't commit any keys, passwords, tokens, usernames, or other secrets