GenerateEstimatePdf passed /dev/stdin as the input filename so lualatex
treats stdin as a regular input file instead of the terminal — without
it, lualatex emergency-stops after the first line of a multi-line
document (the real root cause of the production "Emergency stop", not
bera/luaotfload which were separate host-package gaps already fixed).
EstimatePdf endpoint calls GenerateEstimatePdf directly and streams the
returned FileInfo, guarding on fo.Exists. QueryAcceptanceRequest is
extracted into its own file under ViewModels/FrontOffice.
Add EstimatePdfGenerationTests: unit tests for SignatureToTikz (vector
draws of both signatures) and GenerateEstimatePdf on a devis signed by
both parties — asserts the PDF exists at the expected DestDir path, is
non-empty, and that only the PDF persists (aux/log cleaned). Skips
cleanly when lualatex is absent.
Co-Authored-By: Claude Code <noreply@anthropic.com>