DeFiMath v1.0.4 released - CLZ-based ln, sqrt and sqrtTime

A round of low-level optimizations on the core math primitives:

• ln — rewritten using CLZ (count-leading-zeros)
• sqrt — rewritten using CLZ
• sqrtTime — rewritten using CLZ

Every higher-level function that depends on these primitives — option pricing, Greeks, implied volatility — gets the gas savings transitively.

On the primitives themselves, ln dropped from 508 → 375 gas and sqrt from 344 → 245 gas.

These rewrites are made possible by the new CLZ opcode introduced in EIP-7939, part of the Osaka hard fork — DeFiMath's EVM target has been bumped accordingly.