feat: add colored category badge (Causal/Human/Spatial&Object) in bottom-left meta

app.py

@@ -264,10 +264,29 @@ def _stats_md() -> str:
     )
 
 
+CATEGORY_LABELS = {
+    "casual":         ("Causal",           "#f59e0b"),  # amber
+    "human":          ("Human",            "#3b82f6"),  # blue
+    "spatial_object": ("Spatial & Object", "#10b981"),  # emerald
+}
+
+
+def _category_badge(task: dict[str, Any]) -> str:
+    cat = task.get("category") or "?"
+    label, color = CATEGORY_LABELS.get(cat, (cat, "#6b7280"))
+    return (
+        f'<span style="display:inline-block;padding:4px 12px;border-radius:999px;'
+        f'background:{color};color:#fff;font-weight:600;font-size:14px;'
+        f'letter-spacing:0.3px;">{label}</span>'
+    )
+
+
 def _meta_md(model: str, task: dict[str, Any], state: dict) -> str:
     done_by_me = state.get("submitted_count", 0)
     claimed_n = state.get("claimed_n", 0)
+    badge = _category_badge(task)
     lines = [
+        f"**类别**：{badge}",
         f"**本次会话已提交**：{done_by_me} 条（共已领取 {claimed_n} 条）",
         f"**模型**：`{model}`",
         f"**task_id**：`{task['task_id']}`",