feat: import and export tickets as CSV

Every ticket of a project can be downloaded as CSV, and a CSV exported
from TaskStream or from Jira can be imported: types, statuses, priorities
and people are matched by id or name, the rest falls back with a warning,
and parents are rebuilt. The settings page previews an import before it
creates anything.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

libs/api/tracker/presenters/src/lib/http/dto/requests.dto.ts

@@ -754,6 +754,17 @@ export class UpdateWebhookDto extends PartialType(CreateWebhookDto) {
   active?: boolean;
 }
 
+export class ImportQueryDto {
+  @ApiPropertyOptional({
+    default: false,
+    description: 'Only tell what would be created',
+  })
+  @IsOptional()
+  @Transform(toBoolean)
+  @IsBoolean()
+  dryRun = false;
+}
+
 export class RankIssueDto {
   @ApiPropertyOptional({
     type: String,

libs/api/tracker/presenters/src/lib/http/dto/responses.dto.ts

@@ -194,6 +194,25 @@ export class WebhookCreatedDto {
   secret!: string;
 }
 
+export class ImportLineDto {
+  @ApiProperty({ description: 'Line of the file (the header is 1)' })
+  line!: number;
+  @ApiPropertyOptional() reason?: string;
+  @ApiPropertyOptional() message?: string;
+}
+
+export class ImportReportDto {
+  @ApiProperty({ enum: ['taskstream', 'jira'] }) format!: string;
+  @ApiProperty({ description: 'Nothing was created: a preview' })
+  dryRun!: boolean;
+  @ApiProperty({ description: 'Rows that become tickets' }) rows!: number;
+  @ApiProperty() created!: number;
+  @ApiProperty({ type: [String], example: ['WEB-41', 'WEB-42'] })
+  keys!: string[];
+  @ApiProperty({ type: [ImportLineDto] }) skipped!: ImportLineDto[];
+  @ApiProperty({ type: [ImportLineDto] }) warnings!: ImportLineDto[];
+}
+
 export class GitDeliveryResultDto {
   @ApiProperty({ description: 'Tickets that got something new' })
   recorded!: number;