Modernize Vehicle Framework compatibility

[sviyh]

Modernizes Vehicle Framework compatibility for Vanilla Vehicles Expanded using named VF and Multiplayer actions, shared caravan sessions, and stable vehicle/role references. Synchronizes seats, routes, departure, cargo, passengers, turrets, fuel and flight, and keeps VF path/region work and exit-cell selection deterministic.

Includes the fixes found during VVE QA: restore cargo-tab serialization, buffer fuel-slider changes, resolve role-held pawns for seat assignment and dragging, synchronize turret-target clearing, clear stale flight targeters on world reload, and register the actual abandon action instead of the other-colonist eligibility predicate. The last correction removes the false multiplayer “last colonist” rejection; it does not resolve VF's separate airborne banishment defects.

Both Release projects build without warnings or errors. Retained released-build host/client QA covers caravan departure/return, seats and routes, cargo, fuel, turrets, flight/landing and reconnects, with semantic state checks and delayed desync checks. The released-build matrix is 24 passed, six partial/blocked and one not applicable. Focused A3 follow-up used a development VF build: confirmation/cancel and genuine solo-colonist protection passed in SP/MP; cargo discard and MP arrival remained synchronized.

Remaining framework dependencies: airborne banishment cannot resolve seated pawns in MP and leaves banished pawns aboard in SP; force departure and in-flight cargo require the fixes in SmashPhil/Vehicle-Framework#364 and SmashPhil/Vehicle-Framework#365 to ship and be qualified on released builds; stash recovery seating and empty-ammo reload paths also await released VF fixes. The alternate autoload dialog is feature-disabled. This is not an all-green release sign-off.

Closes #561. Related overlapping work: #592 and #620.