TilesRenderer: Add support for dynamic vertex animation, bounding volume adjustments

If users make changs to the meshes - either via shader or via geometry (eg the flattening plugin) then the bounding hierarchy becomes out of sync and animations will not work. We should support updating tile geometry and updating bounds for traversal dynamically.

Some open questions / questions:

• Should we fire events for dynamic geometry or bounds updates so other plugins can be aware?
• Should we use a custom bounding box intersection function override via plugin?
• Or a margin system?
• Do we need a function to reset bounds back to their original state? Should we bookkeep the overridden bounds vs the originals?
• Should we have some helper function for adjust them?
• Do we need a "dirty" flag for the bounds so we only update the during traversal?

Start by tracing TilesRenderer traversal and the bounding hierarchy, then inspect how the flattening plugin changes tile geometry. Compare shader- and geometry-driven mesh changes and determine how dynamic bounds should be updated during traversal. Done means animated or modified geometry remains traversable with synchronized bounds, with the event, override, reset, helper, and dirty-flag questions resolved.