Clean up unused BMAD workflow, agent, and command files across all IDE
configurations (.agent, .clinerules, .cursor, .gemini, .github, .kilocode,
.opencode) and internal module files (_bmad/bmb, _bmad/bmm).
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Removed mathematical singularity in HeatExchanger models (q_hot - q_cold = 0 was redundant) causing them to incorrectly request 3 equations without internal variables. Fixed ScrewEconomizerCompressor internal_state_len to perfectly align with the solver dimensions.