TSSIM/JESIM final v33 - moment calibration and subsidence footprint fix

Changes from v32:
- Keeps subsidence source nodes stored/exported with slip_m=0, so the down-lobe is not shown as an independent slip node.
- For M0/Mw only, subsidence nodes are counted as rupture-footprint area using the representative slip from non-subsidence source nodes.
- Applies JESIM_MOMENT_CALIBRATION_SCALE = sqrt(8) = 2.8284271247461903 to M0, correcting the observed ~0.30 Mw low bias around Mw 7.5.
- Does not change tsunami initial height or wave physics; this is only the displayed/exported seismic moment magnitude calculation.

Kept from v32/v31:
- 5-minute JESIM observation packets for arrived stations.
- packet_meaningful_update only at packet level; per-station rise remains + or 0.
- Advanced node tuning and multi-select.
- Subsidence nodes show slip_m=0 in source CSV/preset.
- Shimizu removed.
- Transmit-only simulation cap at 60 hours.
- Wall-clock 1x observation transmit timing.
- No y-axis flip.
- Wave-speed 1.13 correction remains rolled back.

Build:
  build_win_mingw.bat
  python jesim_ws_relay.py
