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-core/Cargo.toml

@@ -0,0 +1,24 @@
+[package]
+name = "entropyk-solver-core"
+version = "0.1.0"
+edition = "2021"
+authors = ["Sepehr <sepehr@entropyk.com>"]
+description = "no_std-ready core types for the Entropyk solver: typed convergence taxonomy and shared error types"
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/entropyk/entropyk"
+
+[dependencies]
+thiserror = { version = "2.0", default-features = false }
+serde = { version = "1.0", default-features = false, features = ["derive"] }
+
+[features]
+default = ["std"]
+std = ["alloc", "thiserror/std"]
+alloc = []
+
+[dev-dependencies]
+serde_json = "1.0"
+
+[lib]
+name = "entropyk_solver_core"
+path = "src/lib.rs"