Add major enhancements: UDP streaming, timestamps, labeled variables, RAW/parsed toggle, and recording playback

[kaedros]

This PR introduces several highly requested features that significantly expand the capabilities of SerialAnalyzer beyond basic serial monitoring:

• UDP Input Support: Stream data over network (e.g., from Wi-Fi sensors like ESP32 accelerometers) via configurable port — ideal for wireless and mobile testing. [Feature Request] Add support for UDP data input #13
• Optional Timestamps: Toggle to show timestamps in the live monitor and include them in recorded files. [Feature Request] Timestamp #11
• Labeled Variable Format: Support structured input with headers like time(s),accel_x(m/s²),temp(°C) to auto-generate plot legends and column names. [Feature Request] Ability to receive axis labels from serial data #10
• Display Mode Toggle: Choose between RAW (original byte stream) and Variables (clean parsed values only) in the monitor.
• Recording Playback: Load previously saved .txt recordings for offline analysis, replay, or sharing — using the same parsing and visualization pipeline as live data. [Feature Request] Read input data from a file #12