chore: remove legacy, sync generated config headers, fix inlet kernel

- Remove legacy/ directory (superseded by current architecture).
- Sync auto-generated config headers (config_grid.h, config_objects.h,
  config_method.h, config_physics.h) for current LBMConfig defaults.
- Sync zou_he_local.cuh inlet kernel changes.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/CelerisLab/lbm/kernels/boundary/inlet/zou_he_local.cuh

@@ -17,11 +17,10 @@
 // Free-slip y-walls: at inlet rows y=1 and y=NY-2, pull can source wall nodes for
 // some known directions. Copy those from stored DDF at (x=1, same y) only.
 //
-// NOTE: This helper is NOT Zou-He-specific.  All west inlet schemes that use
+// NOTE: This helper is not Zou-He-specific.  All west inlet schemes that use
 // west_velocity_rho_closure_d2q9() need clean known-direction values.  The
 // free-slip wall interferes with these at the top/bottom inlet corners.
-// Renamed from repair_zou_he_west_knowns_d2q9 for clarity.  The old name is
-// kept for backward compatibility during the transition.
+// The legacy name is kept for now (not renamed yet).
 __device__ inline void repair_zou_he_west_knowns_d2q9(
     float* __restrict__ f,
     const fpxx* __restrict__ fi_in,

src/CelerisLab/lbm/kernels/config/config_grid.h

@@ -6,8 +6,8 @@
 #define NT   256
 #define MULT_GPU 0
 
-#define NX  361
-#define NY  161
+#define NX  512
+#define NY  256
 #define NZ  1
 
 // ---- Lattice model (single source of truth) ----

src/CelerisLab/lbm/kernels/config/config_method.h

@@ -6,18 +6,18 @@
 #define COLLISION_MODEL  0
 #define STREAMING_MODEL  0
 #define STORE_PRECISION  0
-#define USE_DDF_SHIFTING 1
+#define USE_DDF_SHIFTING 0
 
 #define USE_LES 0
 #define LES_CS  0.160000f
 #define LES_CLOSED_FORM 1
 
-#define INLET_PROFILE        0
-#define INLET_SCHEME         3
+#define INLET_PROFILE        1
+#define INLET_SCHEME         0
 #define OUTLET_MODE          0
 #define OUTLET_BLEND_ALPHA   0.700f
 #define OUTLET_BACKFLOW_CLAMP 1
-#define Y_WALL_BC            1
+#define Y_WALL_BC            0
 
 #define OMEGA_COLLISION_MIN 0.01f
 #define OMEGA_COLLISION_MAX 1.990f

src/CelerisLab/lbm/kernels/config/config_objects.h

@@ -3,6 +3,6 @@
 #ifndef CELERIS_CONFIG_OBJECTS_H
 #define CELERIS_CONFIG_OBJECTS_H
 
-#define N_OBJS 1
+#define N_OBJS 0
 
 #endif

src/CelerisLab/lbm/kernels/config/config_physics.h

@@ -4,7 +4,7 @@
 #define CELERIS_CONFIG_PHYSICS_H
 
 #define LBtype float
-#define VIS 0.0090000000
+#define VIS 0.0035000000
 #define RHO 1.0
 #define U0  0.03