Less wall and door destruction snowflake, allows obj to damage walls

Fixes the dev portion of #7538 

Removes the snowflake door and wall damage logic for being hit by emitter projectiles. Replaces randomly dividing projectile damage with a damage cap, and whether a projectile can damage a door is determined by how powerful the projectile is.
I removed the secured_wires multiplier to emitter_hits because it doesn't really make sense that swapping out a different kind of electronics should affect how many hits it takes for the door to be destroyed. If certain doors should be more or less resistant then that can be changed in mapping.