Resolve style/row plugin id without polluting the live view

Pascal Crottrequested to merge
issue/views_bvb-3606577:3606577-non-polluting-resolvers into 1.x

Alternative to !2. Instead of resetting the cached plugins after the fact, this stops them from being polluted in the first place.

The style and row options resolved their fallback plugin id via view->getStyle()/initStyle(), which caches style_plugin/rowPlugin on the shared view — and during early init that grabs the default display's options, so the BVB display's own style/row config got dropped at render.

Fix: resolve the id via the display's own getPlugin(), which never touches the live view. No reset needed in defineOptions().

Closes #3606577

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