Setting $0100 for DashItemCollected shows HJB in menu

[MassHesteria]

Per Cassidy, if we set the $0100 bit of DashItemsCollected, the menu shows hi-jump as collected but equipping it does nothing. Fine for now since we never set that bit, but should be fixed at some point.

[MassHesteria]

Is this really a problem since we don't set the field? The idea with the DashItemsCollected and DashItemsEquipped bitsets was to 100% mimic the vanilla equivalents because the DASH items explicitly correspond to a vanilla item, and using the same bits simplifies the code. We probably don't really need to implement any changes unless we start using bits differently.

[cassidoxa]

My feeling here is that's not urgent or immediately necessary but preferable to square away any side effects that might be hard to predict just in case. Ideally it might at least be documented in sram.asm or somewhere if let's say someone wants to use that bit down the road or if there's some quirk in the implementation that could cause other problems if bits are used. I can look into getting this wrapped up, I feel like I vaguely remember discussing this in the discord and there was some solution that was sort of an extension of how vanilla worked if I'm remembering correctly.

[cassidoxa]

This should be resolved when #68 is merged. Did some slight refactoring of the initial menu drawing code that uses a bitmask to filter out non-DASH slot consideration and otherwise handles the case where we do need to draw something new in the equipment menu.