V149 - Quick FF CSV row/column swap button

Base: v148_m0_x2_from_v145

Changes:
- Added a Quick finite-fault CSV editor button: "Swap row/col".
- The button transposes the whole active grid:
  old cell(row, col) -> new cell(col, row)
  old row count <-> old column count
- Cell contents are preserved: slip, delay, dip, enabled state.
- rel_s / rel_d are recomputed after transpose so rows remain down-dip and columns remain strike.
- The visible 5x5 viewport origin is transposed/clamped too.
- Added UI reminder: rows = down-dip, columns = strike.

Unchanged:
- v148 M0 x2 calibration.
- v145 global 6h damping setting.
- no Okada branch changes.
- no additional wave-height/damping corrections.
