Fix ESLint configuration and dependencies

Problem

ESLint configuration is broken - missing @typescript-eslint/eslint-plugin

Required Fixes

1. Install missing dependencies:

npm install --save-dev @typescript-eslint/eslint-plugin @typescript-eslint/parser

2. Update .eslintrc.json (already done in commit)

Impact

• Blocks git commits (pre-commit lint hook fails)
• Cannot validate TypeScript code style
• Part of infrastructure debt

Acceptance Criteria

• Install @typescript-eslint dependencies
• ESLint runs without errors on staged files
• Pre-commit lint hook passes

Related: #2, #3