Add the modelcraft-decks crate (empty: error type only) (#19)

So the Abaqus, Nastran and LS-DYNA writer tasks add their modules in parallel.


Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm

Co-authored-by: jyviko <2501648+jyviko@users.noreply.github.com>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

crates/decks/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "modelcraft-decks"
+description = "ModelCraft's solver decks: Abaqus input, Nastran bulk data and LS-DYNA keyword writers (and later readers)"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+
+[lints]
+workspace = true
+
+[dependencies]
+modelcraft-model = { workspace = true }
+thiserror = { workspace = true }