feat(timeline): merge bp.systolic + bp.diastolic into single entry

- TimelineEntry.from(indicators:) 批处理:找 bp.systolic 配对同 capturedAt
  (±5s)的 bp.diastolic,合并成 '血压 120/80 mmHg' 一行
- 未配对的 systolic 单独退回 from(indicator:)
- 非 bp.* series 不动
- ArchiveListView + HomeView 改用 from(indicators:) 批处理
- 6 个新测试覆盖配对/未配对/异常标记/非 bp 不动/不同时间不合并

康康/Features/Timeline/TimelineEntry.swift

@@ -57,6 +57,47 @@ struct TimelineEntry: Identifiable, Hashable {
         )
     }
 
+    /// 批处理 Indicator 列表,把 bp.systolic + bp.diastolic 同 capturedAt 合并成
+    /// 一条 "血压 120/80 mmHg" timeline entry。其他 series 逐条 from(indicator:)。
+    /// 合并条件:capturedAt 差 ≤ 5 秒(防止跨次混淆)。
+    static func from(indicators: [Indicator]) -> [TimelineEntry] {
+        var entries: [TimelineEntry] = []
+        var consumed = Set<PersistentIdentifier>()
+
+        // 先找 bp.systolic,配 bp.diastolic
+        for sys in indicators where sys.seriesKey == "bp.systolic" {
+            if consumed.contains(sys.persistentModelID) { continue }
+            guard let dia = indicators.first(where: {
+                $0.seriesKey == "bp.diastolic" &&
+                !consumed.contains($0.persistentModelID) &&
+                abs($0.capturedAt.timeIntervalSince(sys.capturedAt)) <= 5
+            }) else { continue }
+            consumed.insert(sys.persistentModelID)
+            consumed.insert(dia.persistentModelID)
+            entries.append(mergedBP(systolic: sys, diastolic: dia))
+        }
+
+        // 剩下的 indicator(含未配对的 systolic/diastolic、其他 series、自由输入)
+        for i in indicators where !consumed.contains(i.persistentModelID) {
+            entries.append(from(indicator: i))
+        }
+        return entries
+    }
+
+    private static func mergedBP(systolic sys: Indicator, diastolic dia: Indicator) -> TimelineEntry {
+        let abnormal = sys.status != .normal || dia.status != .normal
+        return TimelineEntry(
+            id: "bp-\(sys.persistentModelID)-\(dia.persistentModelID)",
+            kind: .indicator,
+            date: sys.capturedAt,
+            title: "血压",
+            subtitle: "长期监测",
+            trailing: "\(sys.value)/\(dia.value) mmHg" + (abnormal ? " ↑" : ""),
+            trailingIsAlert: abnormal,
+            isOngoing: false
+        )
+    }
+
     static func from(report r: Report) -> TimelineEntry {
         let abnormal = r.indicators.filter { $0.status != .normal }.count
         return TimelineEntry(