Harden Texture Cache Invalidation #787

Summary

Define deterministic cache invalidation and regeneration for resize and DPR changes.

Player and user experience impact

• Player experience: Card visuals remain visible and correctly occluded by overlays using Phaser layer/depth semantics.
• Developer experience: One consistent rendering path with reduced DOM-specific maintenance overhead.

Acceptance Criteria

• Resize and DPR changes trigger expected texture refresh behavior.
• Steady-state rendering avoids unnecessary texture regeneration.
• Cache key/invalidation policy is documented and test covered.

Minimal Implementation (end-to-end slice)

• Define invalidation triggers (resize, DPR change, texture version key).
• Add lightweight regeneration counters/logs in test mode for assertions.
• Add browser smoke coverage for resize and post-resize visual correctness.
• Document cache policy and regeneration triggers.

Dependencies

• Unify Shared SVG Texture Pipeline

Deliverables

• Cache policy docs
• Targeted tests
• Light observability hooks

References

• Parent: Phaser-native rendering for DOM SVG card visuals (replace svgDom) (CG-0MP8YFNX4007N9ZU)