Initial commit: BMAD framework + Story 1.1 Component Trait Definition

Features:
- BMAD (Build Modular AI-driven Development) framework setup
- BMM, BMB, CIS, Core modules configured
- Story 1.1: Component trait with error handling
- Workspace Cargo.toml with components crate
- 31 tests passing (19 unit + 12 doc tests)

Technical:
- Component trait with compute_residuals, jacobian_entries, n_equations
- ComponentError enum with thiserror
- JacobianBuilder for sparse matrix construction
- Object-safe trait supporting Box<dyn Component>
- Comprehensive documentation and examples

_bmad/bmm/teams/team-fullstack.yaml

@@ -0,0 +1,12 @@
+# <!-- Powered by BMAD-CORE™ -->
+bundle:
+  name: Team Plan and Architect
+  icon: 🚀
+  description: Team capable of project analysis, design, and architecture.
+agents:
+  - analyst
+  - architect
+  - pm
+  - sm
+  - ux-designer
+party: "./default-party.csv"