EventPositionExecution should record the fees taken by the position

[hdevalence]

Is your feature request related to a problem? Please describe.

Currently, there's not an easy way to collect data on how much fees each position is earning. For instance, https://dex.penumbra.sevenseas.capital/lp/plpid1c3suelz9xyc4hwh6s0375xrwjkgq9f57z28sy95aj4q6cqu4tjcsfjx8jn is a highly profitable position, but this requires manual inspection.

Describe the solution you'd like

The EventPositionExecution should record data about what fees were claimed by the position during execution. This information is not immediately available (because of the formulation of \gamma as a percentage applied to the inputs) but should be computable from the information that is present.

Ideally, this change could be backported to the 0.79.x branch so that event databases can be regenerated with this field and it can be applied to historical data as well.