Snapshot WIP: solver HP epic progress, BPHX/HX physics, BMAD skill refresh.

Capture uncommitted solver robustness work (regularization, domain errors, linear solver lifecycle, tube DP/MSH), web workbench updates, and synced BMAD skills across IDE agent folders before starting BPHX pressure-drop.

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

crates/solver/Cargo.toml

@@ -10,6 +10,7 @@ repository = "https://github.com/entropyk/entropyk"
 [dependencies]
 entropyk-components = { path = "../components" }
 entropyk-core = { path = "../core" }
+entropyk-solver-core = { path = "../solver-core" }
 nalgebra = "0.33"
 petgraph = "0.6"
 thiserror = "1.0"
@@ -21,7 +22,24 @@ serde_json = "1.0"
 approx = "0.5"
 serde_json = "1.0"
 tracing-subscriber = "0.3"
-entropyk-fluids = { path = "../fluids" }
+entropyk-fluids = { path = "../fluids", features = ["coolprop"] }
+criterion = "0.5"
+
+[[bench]]
+name = "lu_solve"
+harness = false
+
+[[bench]]
+name = "residual_jacobian_assembly"
+harness = false
+
+[[bench]]
+name = "full_solve"
+harness = false
+
+[[bench]]
+name = "batch_solve"
+harness = false
 
 [features]
 # Enables the end-to-end emergent-pressure integration test, which needs a