V116 QUICK FF LEGACY CSV LOAD FIX

Base
- Built from v115.

What changed
- The uploaded/saved CSV format was inspected. It is the legacy list format:
  cell,rel_s,rel_d,slip_m,delay_s,dip_deg
  A1,-2,-2,0.003,12,17
- The loader now explicitly detects that header and parses all following cell-reference rows as legacy list rows.
- The Excel cell address is treated as authoritative; rel_s/rel_d columns are ignored during load.
- Rows/Cols are still read from the comment line when present, and the grid resizes to include all loaded cells.

Expected result for the provided file
- 7 rows x 7 cols.
- 49 finite-fault cells loaded from A1 through G7.
