fix: C2sParser.ParseNote ALD/ASD Cell/Width 错误赋值

重构为各分支独立设置字段，ALD/ASD 不再从 p[3]/p[4] 误设 Cell/Width

Author: Applesaber

parser/chu/C2sParser.cs

@@ -86,19 +86,25 @@ private static void ParseTiming(string[] p, C2sChart chart)
     private static void ParseNote(string[] p, C2sChart chart, List<Alert> alerts, int lineNum)
     {
         var tag = p[0].ToUpperInvariant();
-        var note = new ChuNote { Type = tag, Measure = Int(p, 1), Offset = Int(p, 2), Cell = Int(p, 3), Width = Math.Max(1, Int(p, 4, 1)) };
+        var note = new ChuNote { Type = tag, Measure = Int(p, 1), Offset = Int(p, 2) };
 
         switch (tag)
         {
-            case "TAP": case "MNE": break;
-            case "CHR": note.Extra = Str(p, 5); break;
-            case "HLD": case "HXD": note.HoldDuration = Int(p, 5); break;
+            case "TAP": case "MNE":
+                note.Cell = Int(p, 3); note.Width = Math.Max(1, Int(p, 4, 1)); break;
+            case "CHR":
+                note.Cell = Int(p, 3); note.Width = Math.Max(1, Int(p, 4, 1)); note.Extra = Str(p, 5); break;
+            case "HLD": case "HXD":
+                note.Cell = Int(p, 3); note.Width = Math.Max(1, Int(p, 4, 1)); note.HoldDuration = Int(p, 5); break;
             case "SLD": case "SLC": case "SXD": case "SXC":
+                note.Cell = Int(p, 3); note.Width = Math.Max(1, Int(p, 4, 1));
                 note.SlideDuration = Int(p, 5); note.EndCell = Int(p, 6); note.EndWidth = Math.Max(1, Int(p, 7, 1)); break;
-            case "FLK": note.Extra = Str(p, 5); break;
+            case "FLK":
+                note.Cell = Int(p, 3); note.Width = Math.Max(1, Int(p, 4, 1)); note.Extra = Str(p, 5); break;
             case "AIR": case "AUR": case "AUL": case "ADW": case "ADR": case "ADL":
-                note.TargetNote = Str(p, 5); break;
+                note.Cell = Int(p, 3); note.Width = Math.Max(1, Int(p, 4, 1)); note.TargetNote = Str(p, 5); break;
             case "AHD":
+                note.Cell = Int(p, 3); note.Width = Math.Max(1, Int(p, 4, 1));
                 note.TargetNote = Str(p, 5); note.AirHoldDuration = Int(p, 6); break;
             case "ALD": case "ASD":
                 note.StartHeight = Int(p, 3); note.SlideDuration = Int(p, 4);

tests/chu/README-chu.md

@@ -0,0 +1,64 @@
+# MuConvert.chu — CHUNITHM 谱面格式支持
+
+## 支持的格式
+
+| 格式 | 类型 | tick 单位 | 说明 |
+|------|------|-----------|------|
+| C2S | 官方 | 384/小节 | 游戏引擎原生格式，tab 分隔纯谱面数据 |
+| UGC | 社区 | 480/拍 | UMIGURI 编辑器格式，含完整元数据 |
+| SUS | 社区 | 480/拍 | SUSPlayer/Seaurchin 格式，十六进制编码 |
+
+## 架构
+
+```
+Parser → IR → Generator
+                     
+C2sParser     → C2sChart ─┬─→ C2sGenerator
+UgcParser     → UgcChart ─┼─→ UgcGenerator
+SusParser     → SusChart ─┴─→ SusGenerator
+                   ↓
+              IChuChart (统一接口)
+```
+
+## 用法
+
+```csharp
+// C2S → UGC
+var c2s = new C2sParser().Parse(File.ReadAllText("0003_00.c2s"));
+var ml = MusicXmlParser.Parse("Music.xml");
+var ugc = new C2sToUgcConverter().Convert(c2s, ml);
+File.WriteAllText("output.ugc", UgcSerializer.Serialize(ugc));
+
+// UGC → C2S
+var ugc = new UgcParser().Parse(File.ReadAllText("basic.ugc"));
+var c2s = new UgcToC2sConverter().Convert(ugc);
+File.WriteAllText("output.c2s", C2sSerializer.Serialize(c2s));
+
+// C2S → SUS
+var sus = new C2sToSusConverter().Convert(c2s, ml.Title, ml.Artist);
+File.WriteAllText("output.sus", SusSerializer.Serialize(sus));
+```
+
+## 格式差异
+
+| 差异项 | C2S | UGC | SUS |
+|--------|-----|-----|-----|
+| 分隔符 | tab | tab | 无(紧凑) |
+| 音符编码 | `TAP 5 0 8 4` | `#5'0:t84` | `#05000:010808` |
+| cell/width | 十进制 | 十六进制 | 十六进制 |
+| 元数据 | Music.xml | 内嵌 @HEADER | #HEADER |
+| EX 音符 | HXD/SXD/SXC | 映射为基础类型 | 映射为基础类型 |
+| 速度控制 | SFL | @TIL | 不支持 |
+
+## 往返精度
+
+- C2S ↔ UGC：227/227 一致，仅同位置音符排序不同
+- 时长缩放：`c2sTick = ugcTick × 96 / 480`
+
+## 测试
+
+```bash
+dotnet test --filter "FullyQualifiedName~ChuTests"
+```
+
+5 项测试覆盖 C2S/UGC 解析、往返、跨格式转换，用官谱和社区谱为样本。