Adopt canonical visual stack: 2.5D tactical diorama block scene (art bible + camera contract)

[BrandDead]

Why

The graphics audit (docs/graphics-audit/) found the root cause of the "Atari look": the game has no single declared world-art direction. Pixel sprites, photoreal stills, illustrated boards, glassmorphism UI, and procedural Canvas shapes coexist with no hierarchy, and the 8×8 gameplay grid is the presentation instead of sitting invisibly under a rendered place.

Decision (approved 2026-07-20)

The canonical block view is a cinematic 2.5D oblique "tactical diorama": a fixed high-angle camera over an authored, location-specific block plate (see docs/concept-art/gta_block_board.png and docs/concept-art/1208_w_las_olas_block.webp as the visual targets). The 8×8 grid becomes an invisible/selectively-shown overlay for legal positions. SVG/DOM is reserved for HUD markers, selection rings, and overlays — never for world art or characters.

Scope

• Write an art bible: fixed camera pitch/yaw, orthographic scale, ground plane, lighting direction, palette/LUT, silhouette rules, shadow treatment, registration/pivot conventions, export formats
• Define the actor animation contract: states (idle, walk, aim, fire, hit, dodge, downed, dead, reload, arrested), 4-direction staging minimum, pivots, weapon sockets
• Update docs/ASSET_GENERATION_PROMPTS.md so every generated asset derives from the shared camera/lighting spec (current prompts request isolated cinematic stills that can't composite)
• Build the visual projection layer: grid coordinates → scene coordinates on the authored plate (keep the docs/ARCHITECTURE.md separation of authoritative grid vs. visuals)
• One hero block (Las Olas) rendered end-to-end in the new style as the acceptance bar

Depends on / relates

• Beta gate: art pass, QA, performance, release checklist #45 (beta gate art pass — this issue is the direction that art pass executes)
• Manifest wiring and asset cleanup issues (filed alongside this one)