[CLAUDE] App+Infra+FE-Admin: DynamicForm + .doc/.xls auto-convert on upload

Tier 3 iter2 — form builder UI dùng FieldSpec thay raw JSON textarea.

FE:
- DynamicForm component — parse FieldSpec JSON (record of FieldDef với
  label/type/required/placeholder/hint/options) và render inputs
  dynamic theo type: text/textarea/number/date/currency/select.
- FormsPage render dialog thêm toggle Form ↔ JSON (segmented control).
  Mặc định Form mode khi template có FieldSpec, JSON mode khi không.
  Khi mở dialog cho row khác, reset formValues + chọn đúng default mode.
- parseFieldSpec helper trả { spec, error } — UI báo lỗi nếu JSON
  không parse được, fallback JSON textarea.

BE — generalize converter thành IDocumentConverter:
- IPdfConverter → IDocumentConverter (ConvertAsync(bytes, src, tgt, ct))
  — đủ gánh cả pdf, docx, xlsx targets.
- LibreOfficeDocumentConverter — 1 shell-out pattern cho mọi conversion
  (docx→pdf, doc→docx, xls→xlsx, xlsx→pdf), target arg truyền vào
  --convert-to.
- ExportTemplatePdfCommand update dùng "pdf" target.

Auto-convert .doc/.xls trên upload:
- Validator accept thêm .doc/.xls (thêm note "sẽ tự convert").
- UploadContractTemplateCommandHandler: nếu ext là doc/xls → read stream
  → converter.ConvertAsync → lưu file .docx/.xlsx thay vì format gốc.
  File rendering pipeline (DocxRenderer/XlsxRenderer) chỉ support docx/
  xlsx — convert đảm bảo consistent.
- Display FileName preserve original name nhưng đổi extension.

Unblock 3 file .doc legacy template — admin giờ upload .doc bình thường,
system tự convert.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/Backend/SolutionErp.Application/Common/Interfaces/IPdfConverter.cs

@@ -1,9 +1,14 @@
 namespace SolutionErp.Application.Common.Interfaces;
 
-// Convert .docx/.xlsx bytes to PDF. The Infrastructure impl shells out to
-// LibreOffice headless (soffice.exe --headless --convert-to pdf). Future swap:
-// QuestPDF re-render if we want zero external dep, or Aspose.Words for quality.
-public interface IPdfConverter
+// Convert document bytes between office formats. Infrastructure impl shells out
+// to LibreOffice headless (soffice.exe --headless --convert-to TARGET).
+//
+// Supported source/target combos are whatever LibreOffice supports, commonly:
+//   docx → pdf, doc → docx, xlsx → pdf, xls → xlsx
+//
+// Future swap: QuestPDF for PDF-only, Aspose.Words for quality, or cloud API —
+// without touching callers.
+public interface IDocumentConverter
 {
-    Task<byte[]> ConvertAsync(byte[] sourceBytes, string sourceExt, CancellationToken ct = default);
+    Task<byte[]> ConvertAsync(byte[] sourceBytes, string sourceExt, string targetExt, CancellationToken ct = default);
 }

src/Backend/SolutionErp.Application/Forms/FormFeatures.cs

@@ -106,7 +106,7 @@ public record ExportTemplatePdfCommand(Guid TemplateId, Dictionary<string, strin
 public class ExportTemplatePdfCommandHandler(
     IApplicationDbContext db,
     IFormRenderer renderer,
-    IPdfConverter pdfConverter,
+    IDocumentConverter converter,
     IWebHostEnvironmentLocator envLocator) : IRequestHandler<ExportTemplatePdfCommand, RenderResult>
 {
     public async Task<RenderResult> Handle(ExportTemplatePdfCommand request, CancellationToken ct)
@@ -120,7 +120,7 @@ public class ExportTemplatePdfCommandHandler(
             throw new NotFoundException($"File template không tồn tại: {tpl.StoragePath}");
 
         var rendered = await renderer.RenderAsync(absPath, tpl.Format, request.Data, "source", ct);
-        var pdfBytes = await pdfConverter.ConvertAsync(rendered.Content, tpl.Format, ct);
+        var pdfBytes = await converter.ConvertAsync(rendered.Content, tpl.Format, "pdf", ct);
         var outName = $"{tpl.FormCode}.pdf";
         return new RenderResult(pdfBytes, outName, "application/pdf");
     }
@@ -142,7 +142,11 @@ public record UploadContractTemplateCommand(
 public class UploadContractTemplateCommandValidator : AbstractValidator<UploadContractTemplateCommand>
 {
     private const long MaxBytes = 10L * 1024 * 1024;
-    private static readonly HashSet<string> AllowedFormats = new(StringComparer.OrdinalIgnoreCase) { ".docx", ".xlsx" };
+    // .doc/.xls accepted — auto-converted to .docx/.xlsx during upload handling.
+    private static readonly HashSet<string> AllowedFormats = new(StringComparer.OrdinalIgnoreCase)
+    {
+        ".docx", ".xlsx", ".doc", ".xls",
+    };
 
     public UploadContractTemplateCommandValidator()
     {
@@ -155,7 +159,7 @@ public class UploadContractTemplateCommandValidator : AbstractValidator<UploadCo
             .WithMessage("Template tối đa 10 MB.");
         RuleFor(x => x.FileName).NotEmpty()
             .Must(name => AllowedFormats.Contains(Path.GetExtension(name)))
-            .WithMessage("Chỉ chấp nhận file .docx hoặc .xlsx.");
+            .WithMessage("Chỉ chấp nhận file .docx/.xlsx (.doc/.xls sẽ tự convert).");
         RuleFor(x => x.FieldSpec).Must(BeValidJsonOrNull)
             .WithMessage("FieldSpec phải là JSON hợp lệ (hoặc để trống).");
     }
@@ -170,6 +174,7 @@ public class UploadContractTemplateCommandValidator : AbstractValidator<UploadCo
 
 public class UploadContractTemplateCommandHandler(
     IApplicationDbContext db,
+    IDocumentConverter converter,
     IWebHostEnvironmentLocator env) : IRequestHandler<UploadContractTemplateCommand, ContractTemplateDto>
 {
     public async Task<ContractTemplateDto> Handle(UploadContractTemplateCommand request, CancellationToken ct)
@@ -178,17 +183,27 @@ public class UploadContractTemplateCommandHandler(
         if (await db.ContractTemplates.AnyAsync(t => t.FormCode == request.FormCode, ct))
             throw new ConflictException($"FormCode '{request.FormCode}' đã tồn tại.");
 
-        var ext = Path.GetExtension(request.FileName).TrimStart('.').ToLowerInvariant();
+        var srcExt = Path.GetExtension(request.FileName).TrimStart('.').ToLowerInvariant();
+
+        // Auto-convert legacy .doc/.xls → .docx/.xlsx so rendering pipeline
+        // (DocxRenderer / XlsxRenderer) works uniformly. Admin sees the upload
+        // succeed with the new format without extra steps.
+        var (finalBytes, finalExt) = (srcExt is "doc" or "xls")
+            ? await ReadAndConvert(request.Content, srcExt, ct)
+            : (await ReadAllBytes(request.Content, ct), srcExt);
+
         var id = Guid.NewGuid();
-        // Store using a deterministic name — FormCode avoids path-traversal
-        // (already regex-validated above) and disambiguates files.
-        var safeFile = $"{request.FormCode}_{id:N}.{ext}";
+        var safeFile = $"{request.FormCode}_{id:N}.{finalExt}";
         var templatesDir = Path.Combine(env.WebRootPath, "templates");
         Directory.CreateDirectory(templatesDir);
         var absPath = Path.Combine(templatesDir, safeFile);
 
-        await using (var fs = File.Create(absPath))
-            await request.Content.CopyToAsync(fs, ct);
+        await File.WriteAllBytesAsync(absPath, finalBytes, ct);
+
+        // Preserve original filename for user display but reflect final format.
+        var displayName = srcExt != finalExt
+            ? Path.ChangeExtension(request.FileName, finalExt)
+            : request.FileName;
 
         var entity = new Domain.Forms.ContractTemplate
         {
@@ -196,9 +211,9 @@ public class UploadContractTemplateCommandHandler(
             FormCode = request.FormCode,
             Name = request.Name,
             ContractType = request.ContractType,
-            FileName = request.FileName,
+            FileName = displayName,
             StoragePath = $"templates/{safeFile}",
-            Format = ext,
+            Format = finalExt,
             FieldSpec = request.FieldSpec,
             Description = request.Description,
             IsActive = true,
@@ -210,6 +225,21 @@ public class UploadContractTemplateCommandHandler(
             entity.Id, entity.FormCode, entity.Name, entity.ContractType,
             entity.FileName, entity.Format, entity.FieldSpec, entity.Description, entity.IsActive);
     }
+
+    private static async Task<byte[]> ReadAllBytes(Stream s, CancellationToken ct)
+    {
+        using var ms = new MemoryStream();
+        await s.CopyToAsync(ms, ct);
+        return ms.ToArray();
+    }
+
+    private async Task<(byte[] Bytes, string Ext)> ReadAndConvert(Stream s, string srcExt, CancellationToken ct)
+    {
+        var srcBytes = await ReadAllBytes(s, ct);
+        var targetExt = srcExt switch { "doc" => "docx", "xls" => "xlsx", _ => srcExt };
+        var converted = await converter.ConvertAsync(srcBytes, srcExt, targetExt, ct);
+        return (converted, targetExt);
+    }
 }
 
 // ========== UPDATE metadata + FieldSpec ==========