v1.9.2 - 3D graph toolbar, .DAT graph menu, image-to-TEX fix

See CHANGELOG.md for the full list of changes. Highlights: 3D graph toolbar (Node / -Node / Nodes / Links / Total Nodes / Total Links shown when a graph*.dat is loaded); .DAT context menu now detects graph*.dat and offers Export to JSON / Export to Table (.md); 'Pack to .res archive' renamed to 'Pack to Archive' and auto-saves to a sibling .res; image-to-TEX error log now reports input -> output and shows a critical message. All 57 tests pass.