Graph generation: next steps forward

[yakra]

Setup

• Edge compression: extraneous stuff #269
• devel systems in subgraph CSVs TravelMapping/DataProcessing#614
• Region & System vertex population #265 Phase 1
• Region & System edge population #285

Subgraph efficiency, lightweight

• Either use or nix HGEdge::segment_name TravelMapping/DataProcessing#589
• unique_name -> char*
• GLE region/system lists -> vectors
• concurrency lists -> vectors
• Use memset instead of a for loop to zero out cbycode.
• C arrays for HGEdge::intermediate_points #264
• collapsed edges outside area graph radius TravelMapping/DataProcessing#613
• traveler nums
• Nix traveler_lists vector
• vertex numbers #255
• Redundancy in tmg edge line computation #286
• Try fmt::format_int and {fmt}'s std::ofstream support.

Subgraph efficiency, heavyweight

• TMBitset<HGVertex*> #251
• TMBitset<HGEdge*>