Add new regression and ensemble experiment configurations for V2-M and OrthoBridge

- Introduced multiple regression experiment configurations targeting vf_md, including:
  - cd_solo_reg_set.json: CD tower only regression setup.
  - img_solo_reg_set.json: Image tower only regression setup.
  - reg_head_epoch_sweep.json: Baseline regression sweeps at different epochs (50, 75, 100).
  - reg_head_set.json: Various regression setups including baseline and OrthoBridge configurations.
  - single_eye_reg.json: Single-eye regression setup for worst-eye aggregation analysis.

- Added ensemble configurations for OrthoBridge with different inner bridges:
  - ortho_alts_ensemble.json: Ensemble tests with ConcatBridge, PairwiseAdditiveBridge, and GatedAdditiveBridge.
  - ortho_alts_tritower.json: Tritower tests with the same inner bridges.

- Created V2-M specific configurations:
  - baseline_reg_nt50.json: Regression baseline with V2-M backbone.
  - geom_vec_gt.json and geom_vec_unet.json: Geometry vector injection experiments with V2-M.
  - single_l1_bridges.json: Single-eye ensemble experiments with various bridge types.
  - tritower_geom_gt.json: Tritower setup with GT contour-rasterized masks.

- Promoted existing experiments to higher repetitions for robustness.

v4/figures/output/md_importance_phase5.csv

@@ -0,0 +1,10 @@
+feature,mean_importance,std_importance
+Age,0.03184101084778838,0.017362350323790826
+IOP_corr,0.0209298093602393,0.01619384191432414
+Gender,0.010245143460808846,0.020271910566046904
+Phakic/Pseudophakic,0.005718439848904106,0.019878985551523384
+eyeID,0.002907359675067821,0.0068517202428395665
+Pachymetry,0.0027483776870354105,0.008864856763204554
+dioptre_2,8.49432781653429e-05,0.0010216320594945336
+astigmatism,-0.0012830897957007016,0.0044473592790778
+dioptre_1,-0.002925119731183013,0.006220349074293031