Module arena 

Walks the profile trace directory and materializes the DebugSession the TUI consumes.

Shares the core PC-driven call-stack algorithm with the flamegraph renderer via [crate::flamegraph::trace::stream_trace]. The two consumers differ only in their sink: the SVG folder aggregates into flat (stack → cu) maps, and this module emits one DebugStep per traced instruction plus DWARF-resolved source locations.

Functions

build_session

Build the session from <profile_dir>/<test_name>/ trace directories.