fix(telegram): 修復 Telegram 卡片 description 顯示 debug garbage

問題：description = debate_summary[:500]，用戶看到的是內部審計文字
修復：從 diagnosis.top_hypothesis + action_plan.top_candidate 組出人類可讀摘要
格式：「根因：[描述]（信心 X%）；方案：[動作]」

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/api/src/services/decision_manager.py

@@ -983,16 +983,31 @@ def _package_to_proposal_data(package: Any) -> dict[str, Any]:
     else:
         risk_level = "high"
 
+    # 組出人類可讀的 description（Telegram 卡片顯示用）
+    # 2026-04-16 ogt + Claude Sonnet 4.6: 修復 description=debate_summary garbage
+    diag = getattr(package, "diagnosis", None)
+    plan = getattr(package, "action_plan", None)
+    desc_parts = []
+    if diag and getattr(diag, "top_hypothesis", None):
+        h = diag.top_hypothesis
+        desc_parts.append(f"根因：{h.description[:150]}（信心 {h.confidence:.0%}）")
+    if plan and getattr(plan, "top_candidate", None):
+        c = plan.top_candidate
+        desc_parts.append(f"方案：{c.action[:100]}")
+    if package.blocked_reason:
+        desc_parts.append(f"備注：{package.blocked_reason[:100]}")
+    description = "；".join(desc_parts) if desc_parts else (action[:200] if action else "待分析")
+
     return {
         "action": action,
         "kubectl_command": action if action.startswith("kubectl") else "",
-        "description": package.debate_summary[:500] if package.debate_summary else "",
+        "description": description,
         "reasoning": package.debate_summary[:1000] if package.debate_summary else "",
         "confidence": confidence,
         "risk_level": risk_level,
         "source": "phase2_agent_debate",
         "requires_human_review": package.requires_human_approval,
-        # Phase 2 診斷摘要（供 Telegram 卡片顯示）
+        # Phase 2 診斷摘要（供 Audit Trail / 學習閉環，不直接顯示給用戶）
         "debate_summary": package.debate_summary or "",
         "all_agents_degraded": package.all_agents_degraded,
         "blocked_reason": package.blocked_reason or "",