It's not possible to create new feats that do much of anything. Most feat mechanics are hard-coded in the engine, and the feat itself is just a signal to the engine that whether a character has the feat.
There is a script function to grant the player permanent bonus Force Points in KOTOR 2, but not KOTOR 1. There is no script which is fired whenever a character levels up, but there are scripts that run every few seconds (e.g. the player's heartbeat script) which could be edited to replicate such an effect. There would be compatibility issues with other mods, though.