Logic changes and general rewrite

[collin-b1]

• Rework camera state machine and fix context transition bugs
• Track active contexts (riding, flying, swimming, crawling) in a priority-ordered map polled each tick, replacing the mount/pose event hooks. Fixes wrong perspective restores across context transitions, stale exit animations on remount, the F5 state leak, and camera switches on failed mounts.
• Animate zoom as a fraction of vanilla's collision-clamped distance, replace the broken float config sliders with 1-100% speed values, and drop unused mixin configs and template leftovers.