feat(migration): add skip rows option to CSV import

Allow users to skip the first N data rows when importing CSV files.
This is useful when the CSV contains metadata rows before the actual
task data begins. Adds skip_rows to ImportConfig (backend) and a
number input in the parsing options UI (frontend).

frontend/src/i18n/lang/en.json

@@ -676,6 +676,7 @@
       "parsingOptions": "Parsing Options",
       "delimiter": "Delimiter",
       "dateFormat": "Date Format",
+      "skipRows": "Skip Rows",
       "mapColumns": "Map Columns",
       "example": "e.g.",
       "preview": "Preview",

frontend/src/services/migrator/csvMigration.ts

@@ -46,6 +46,7 @@ export interface ImportConfig {
 	delimiter: string
 	quote_char: string
 	date_format: string
+	skip_rows: number
 	mapping: ColumnMapping[]
 }
 

frontend/src/views/migrate/MigrationCSV.vue

@@ -82,6 +82,17 @@
 							</select>
 						</div>
 					</div>
+					<div class="option-group">
+						<label for="skipRows">{{ $t('migrate.csv.skipRows') }}</label>
+						<input
+							id="skipRows"
+							v-model.number="config.skip_rows"
+							type="number"
+							class="input"
+							min="0"
+							@change="updatePreview"
+						>
+					</div>
 				</div>
 			</div>
 
@@ -219,6 +230,7 @@ const config = ref<ImportConfig>({
 	delimiter: ',',
 	quote_char: '"',
 	date_format: '2006-01-02',
+	skip_rows: 0,
 	mapping: [],
 })
 
@@ -303,6 +315,7 @@ async function handleFileUpload() {
 			delimiter: result.delimiter,
 			quote_char: result.quote_char,
 			date_format: result.date_format,
+			skip_rows: 0,
 			mapping: result.suggested_mapping,
 		}
 
@@ -366,6 +379,7 @@ function resetToUpload() {
 		delimiter: ',',
 		quote_char: '"',
 		date_format: '2006-01-02',
+		skip_rows: 0,
 		mapping: [],
 	}
 }

pkg/modules/migration/csv/csv.go

@@ -127,6 +127,7 @@ type ImportConfig struct {
 	Delimiter  string          `json:"delimiter"`
 	QuoteChar  string          `json:"quote_char"`
 	DateFormat string          `json:"date_format"`
+	SkipRows   int             `json:"skip_rows"`
 	Mapping    []ColumnMapping `json:"mapping"`
 }
 
@@ -396,6 +397,17 @@ func PreviewImport(file io.ReaderAt, size int64, config *ImportConfig) (*Preview
 		return nil, &migration.ErrNotACSVFile{}
 	}
 
+	// Skip rows if configured
+	if config.SkipRows > 0 {
+		if config.SkipRows >= len(rows) {
+			return &PreviewResult{
+				Tasks:     []PreviewTask{},
+				TotalRows: 0,
+			}, nil
+		}
+		rows = rows[config.SkipRows:]
+	}
+
 	result := &PreviewResult{
 		Tasks:     make([]PreviewTask, 0, minInt(5, len(rows))),
 		TotalRows: len(rows),
@@ -566,6 +578,15 @@ func MigrateWithConfig(u *user.User, file io.ReaderAt, size int64, config *Impor
 		return &migration.ErrNotACSVFile{}
 	}
 
+	// Skip rows if configured
+	if config.SkipRows > 0 {
+		if config.SkipRows >= len(rows) {
+			rows = nil
+		} else {
+			rows = rows[config.SkipRows:]
+		}
+	}
+
 	if len(rows) == 0 {
 		return &migration.ErrFileIsEmpty{}
 	}