BmpHeader.ReadDims reads texture dims from the pre-converted BMP header (VM-
thread-safe, no pixel decode) — the data source for GetTextureSize. `Age.Cli gfx
<SCENE>` runs a scene and dumps set-texture/get-texture-size/draw-texture in
order with resolved file + computed geometry, mirroring the `audio` diagnostic.
Confirms 0x208 now yields real dims (800x600/800x800/800x227) and sane UI
geometry; surfaces the first-load anchor edge (unseeded state, Phase B).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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