[ECONOMIC] PoL Savers Insta-Match

Security

A security researcher was able to demonstrate on TC mainnet a profitable trading strategy on poorly-arbed pools using a specific synth-mint arb loop.

This fix is made to address this loop. When a savers enters the pool, the PoL should insta-match the entry. This means there is no longer a price-change on synth-mint. Trade assets addresses this separately.

Faster PoL deploy

This also allows the PoL to more quickly scale (deploy capital into the pool faster) without causing the PoL to slip when it enters.

Implementation

When a Synth is minted, detect the priceInRune and insta-add the equivalent amount of RUNE from the PoL in the same block.