feat(wasm): expose solved array current distribution

[andrekuehne]

Summary

• add getCurrentDistribution for the latest solved array-facade solution
• return exact complex A/B/C coefficients, physical segment centres and directions, caller tags, native indices, and decoded connections
• preserve exact current ordering across explicit and symmetry-expanded representations
• bump the WASM package to 0.6.0 and document the additive API

Compatibility

• NEC2++ engine remains 2.5.0
• WASM ABI remains 1
• no native symbols or binary result formats change

Validation

• 135 package tests passed
• 6 packed-consumer tests passed
• explicit/symmetric complex-current parity and position-sensitive phase are covered
• independent review: ACCEPT