Lossless EPANET round-trip fidelity

Sections EPANET understands but DekEn doesn't yet model pass through an import/export cycle verbatim, and pattern multipliers, pump speed-affinity laws (Q∝N, H∝N²), and STATUS/GPV/POWER controls are preserved rather than silently re-solved or dropped.

• Handing a DekEn-edited network back to a team still working primarily in EPANET
• Confirming that editing one part of a network in DekEn didn't quietly alter an unrelated section
• Any workflow where the .inp file needs to stay a faithful record, not just "close enough"

Unmodeled sections are stored and re-emitted byte-for-byte on export; pump affinity laws and demand/control patterns are represented internally rather than flattened into a single operating point.