Improve short-occlusion recovery for moving nameplates

[taocihei]

Problem

OCR can disappear for several frames during combat effects, motion blur, or occlusion. Linear interpolation only works when observations on both sides belong to the same target.

Desired direction

• Associate sparse OCR detections with a visual tracker
• Bridge short occlusions without drifting to nearby nameplates
• Emit confidence per interval
• Mark uncertain ranges for review instead of silently masking the wrong region

Acceptance criteria

• Unit tests with synthetic crossing/occlusion tracks
• No interpolation across unrelated same-name HUD/chat instances
• Configurable maximum recovery gap
• Runtime measured on a 1080p/60 FPS sample

中文：希望把 OCR 稀疏检测与视觉跟踪结合，在强特效遮挡期间补全轨迹，并把不确定区间交给用户复核。