Add dftracer_compact_by_pid Script

[izzet]

• Added dftracer_compact_by_pid script to compact trace files by process ID.
• Updated documentation with usage instructions for the new script.
• Included script installation command in CMakeLists.txt.
• Added the script to setup.py (auto-formatted as per VSCode settings).

Sample output:

Setting up output directory
Found 384 trace files. Now grouping them by process ID...
Processing PID 1009615 with 10000000 lines per file...
Processing PID 1009616 with 10000000 lines per file...
Processing PID 1009617 with 10000000 lines per file...
...
Compressing files...