V129 CSV DIP BULK APPLY + STATION 49 OVERRIDE + NO SHALLOW DAMPING

Base
- Built from v127_validated_depth_efficiency_table.
- Keeps scalar source model; no Okada changes are included.

Changes
1) Quick finite-fault CSV/grid editor
- Added "Dip all" input and "Apply dip to active" button.
- The button reads the dip value in the CSV editor and applies it to every active slip cell in the whole quick-FF grid, including cells outside the current 5x5 viewport.
- Valid dip range is 5..60 degrees.

2) Observation station-id / forecast-zone override
- Final user override sets station_no 1500, 1501, 1502, and 1524 to station_id 49.
- The override is applied last, after automatic hole filling, so these four stations are not pulled back to neighboring zones.

3) Shallow-water damping removed
- Removed the v126 depth-based shallow-coast damping curve from coastal_reflection_keep_for_cell().
- Water cells no longer receive the extra <120m shallow-depth loss.
- Coast absorb UI/settings are left in place for compatibility, but this shallow-water damping path now returns hard-wall reflection for visible coastline cells.

Build
- Windows: run build_win_mingw.bat with MinGW-w64 GCC.
