Add TODO.md with codebase improvement roadmap

[Copilot]

Analyzed the DarkStream distributed video converter codebase and documented actionable improvements organized by priority and domain.

Categories covered

• Core Architecture - inotify file watching, worker auth, job priority queue, graceful shutdown
• Security - API authentication, HTTPS, rate limiting, path traversal hardening
• Monitoring - Prometheus metrics, Grafana dashboards, OpenTelemetry tracing
• Video Processing - input validation, progress reporting, AV1/WebM support, thumbnails
• CLI - interactive mode, JSON output, shell completion
• Deployment - Kubernetes manifests, ARM64 builds, Docker health checks
• Testing - coverage targets, integration tests, fuzzing, load tests
• Performance - connection pooling, job polling optimization, chunked streaming

Structure

Each section uses High/Medium/Low priority tiers. Known issues and a version roadmap (v1.1, v1.2, v2.0) are included at the end.

Original prompt

analyze the codebase of this project and make me a todo.md file

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