[CANGEN/Daedalus] - Optimize vec allocation

[harrison-e]

Description

Right now, the Daedalus sub-functions in libs/calypso-cangen/ are poorly optimized. Particularly, in can_gen_decode.rs, the code generated reuses one Vec named decoded_points, which is cloned into each new DecodeData for the return value, and then cleared for its next use. This is inefficient!!

Acceptance Criteria

Functionality of Daedalus is preserved, without using/reusing decoded_points.

Proposed Solution

One idea is to make a new Vec for each NetField and use that in the construction of the DecodeData struct for the result. It shouldn't be super hard to figure this one out though so I will leave the fun to whoever wants this ticket!