Extend analyze command to handle subtree files

[javagl]

The analyze command currently accepts tile content files, and dumps out a set of (unspecified!) files with low-level, technical information for debugging.

I found that .subtree files are ... among the hardest to analyze in practice. The analyze command could be extended to extract at least some information from these files.

Most of the related structures and classes in the 3D Tiles Tools - namely, the ones in the implicitTiling package - have basically been ported from Java to TypeScript, from one of my private/internal projecs (called J3DTiles). This already does have some utilities for dumping out some debug information for .subtree files. This is currently in a crude form, like this...

Content at (level=0, (0,0,0)) is not available
...
Content at (level=2, (0,0,0)) is not available
Content at (level=2, (1,0,0)) is not available
Content at (level=2, (2,0,0)) is available
Content at (level=2, (3,0,0)) is not available
Content at (level=2, (0,1,0)) is not available
...
Content at (level=2, (2,1,1)) is not available
Content at (level=2, (3,1,1)) is available
Content at (level=2, (0,2,1)) is not available
Content at (level=2, (1,2,1)) is not available
...
Content at (level=2, (3,3,3)) is not available
Tile availability bits:  10100000 00000000 01000000 10000000 00000000 00000000 00000000 00000000 00000000 0
Tile at (level=0, (0,0,0)) is available and should be available
Tile at (level=1, (0,0,0)) is not available and should not be available
Tile at (level=1, (1,0,0)) is available and should be available
Tile at (level=1, (0,1,0)) is not available and should not be available
...
Tile at (level=2, (1,0,0)) is not available and should not be available
Tile at (level=2, (2,0,0)) is available and should be available
Tile at (level=2, (3,0,0)) is not available and should not be available
...

But this could be done, in a similar form, by the 3D Tiles Tools analyze command.

One difficulty here is that interpreting the subtree files requires (external!) information about whether the data refers to a quadtree or an octree (and maybe the number of levels that are expected). But one could consider applying some "heuristics"/guesses, or in doubt, supply that information directly at the command line.

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An aside: I personally prefer the more "visual" approach here, including a viewer/editor for quadtree subtree data...

... but (this is difficult for octrees, and) even just dumping out this information in the console/text file could be helpful for debugging.