Add comprehensive package management system for updating all dependencies

[Copilot]

This PR implements a complete package management system to address the need for updating all npm packages in the YouTube Subscriptions Transfer extension.

What's Added

New NPM Scripts

• npm run outdated - Check which packages have updates available
• npm run update-check - Check outdated packages and security vulnerabilities
• npm run update-safe - Safe updates with security fixes (recommended)
• npm run update-minor - Update to latest minor/patch versions
• npm run update-major - Update all packages to latest versions (use with caution)
• npm run update-interactive - Interactive package update selection
• npm run update-demo - Show demo of available update commands
• npm run verify-update - Automated post-update verification

Helper Scripts

• scripts/update-demo.sh - Interactive demo showing all update options
• scripts/verify-update.sh - Automated verification that runs TypeScript checks, builds the extension, and validates output

Documentation

• Added comprehensive "Package Management" section to README with step-by-step instructions
• Created PACKAGE_UPDATES.md with detailed update history and notes on major version changes
• Documented which packages require careful consideration for major updates (TailwindCSS 4.x, Zod 4.x, etc.)

Packages Updated

Successfully updated 11 packages to their latest compatible versions:

• @crxjs/vite-plugin: 2.0.2 → 2.2.0
• @types/node: 22.16.0 → 22.17.2
• axios: 1.10.0 → 1.11.0
• pino: 9.7.0 → 9.9.0
• svelte: 5.35.1 → 5.38.2
• typescript: 5.8.3 → 5.9.2
• vite: 7.0.1 → 7.1.3
• And 4 more packages

Bug Fixes

Fixed TypeScript compatibility issues that surfaced with updated packages:

• Updated Pino logger calls to use template strings instead of multiple parameters
• Fixed logger calls in src/utils/communication.ts and src/background/background.ts

Testing

• ✅ Extension builds successfully after updates
• ✅ Development server works correctly
• ✅ TypeScript checks pass
• ✅ All existing functionality preserved

Usage Examples

Check for updates:

npm run update-check

Perform safe updates:

npm run update-safe

Verify everything works after updates:

npm run verify-update

This system provides a safe, documented workflow for keeping the extension's dependencies up to date while minimizing the risk of breaking changes.

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