catalog: fill optional 2D fields (camera_perspective, grid_dimensions)

[TMHSDigital]

16 of 54 2D entries have no camera_perspective, which weakens the perspective filter (e.g. kenney-1-bit-pack, kenney-pixel-vehicle-pack, lpc-revised-basics). Several tile-grid packs have no grid_dimensions (e.g. ansimuz-sunnyland, kenney-roguelike-characters, lpc-revised-basics). Worth a sweep; each value should come from the source page.

[TMHSDigital]

Partly done in #49, from the source pages only (read 2026-09-26): bondoki-rotating-gems grid 52x52 ("size per tile is 52x52 pixels"), lpc-revised-basics camera isometric_3_4 (the author's repo: "three-quarters (top-down) perspective"). The rest stay unset because their pages do not state a view or tile size (several Kenney packs, kenney-roguelike-characters, ansimuz-sunnyland), or have no single honest value (aggregators, multi-perspective packs). Filling them needs a person looking at the files.

[TMHSDigital]

Checked again in the open-issues sweep (#51): nothing more can be filled from source pages alone. The entries still missing camera_perspective or grid_dimensions either don't state a view or tile size on their pages (several Kenney packs, kenney-roguelike-characters, ansimuz-sunnyland) or have no single honest value (aggregators, multi-perspective packs). Each needs someone to open the files and look. Keeping this open as a good first issue.