Before this commit, the call view arranged its cards by rewriting CSS variables. Cards jumped to their new place instead of moving to it, and a rearrangement recreated their elements, so a video glitched and restarted from scratch on every layout change.

This commit fixes the issue by computing the rendering outside the component, around three concepts:

- the "stage" is the one area a call renders into, shared by the tile grid, the sidebar that reserves its room out of the grid's, and the inset overlaying the first tile;
- a "surface" is one entry of that stage, held by a stable identity rather than by its position, so a layout change moves it, media and all, instead of recreating it;
- a "profile" is the set of layout knobs a call resolves to, one per place it renders in: Discuss, meeting, chat window, PiP and phone.

Four modules carry them:

1. `call_profile.js` resolves the call into a `CallProfile`, the knobs everything else runs on: adding a profile is a new `CALL_PROFILE_TYPE` and a new case, never a branch elsewhere.
2. `stage/surface_manager.js` reconciles the desired surfaces with the live ones, so a video travels grid <-> sidebar <-> spotlight without being torn down.
3. `stage/layout_engine.js` turns the profile, the measured stage and the desired surfaces into rectangles. Deterministic and side-effect free.
4. `stage/geometry_renderer.js` applies those rectangles through the Web Animations API, outside the render loop, so surfaces move on the compositor instead of jumping.

This commit also makes these miscellaneous changes:

- the spotlight splits its stage between the recent speakers, kept 3s after they stop talking, instead of swapping on every sentence;
- cards are ordered by what the stage must not hide: presenters, then speakers in the order they took the floor, then self;
- the inset snaps to the nearest corner, stored as a corner rather than pixels, so it survives a resize;
- on a small screen the call bar folds everything but the microphone, the camera and their settings into one "More" menu;
- "Switch Camera" moves into the quick video settings;
- in a chat window, the fullscreen button no longer pulses to nudge the user into it when another participant turns their camera on.

task-4781315

Forward-Port-Of: odoo/odoo#282766