feat(scenario): add scenario runs, run steps, and step ordering

- add ScenarioRunEntity (pending|in_progress|pass|fail) and ScenarioRunStepEntity (waiting|pending|in_progress|pass|fail)
- add POST /scenarios/:id/run — creates run with first step pending, rest waiting
- add order field to ScenarioStepEntity and ScenarioRunStepEntity for deterministic sequential execution
- findOne and createRun now sort steps/stepRuns by order ASC

src/scenario/dto/create-scenario-step.dto.ts

@@ -1,8 +1,13 @@
 import { ApiProperty, ApiPropertyOptional } from '@nestjs/swagger';
-import { IsIn, IsNotEmpty, IsOptional, IsString } from 'class-validator';
+import { IsIn, IsInt, IsNotEmpty, IsOptional, IsString, Min } from 'class-validator';
 import { StepType } from '../scenario-step.entity';
 
 export class CreateScenarioStepDto {
+  @ApiProperty({ example: 0, description: 'Execution order (ascending)' })
+  @IsInt()
+  @Min(0)
+  order: number;
+
   @ApiProperty({ enum: ['login', 'exec'], example: 'exec' })
   @IsIn(['login', 'exec'])
   type: StepType;

src/scenario/dto/update-scenario-step.dto.ts

@@ -1,8 +1,14 @@
 import { ApiPropertyOptional } from '@nestjs/swagger';
-import { IsIn, IsNotEmpty, IsOptional, IsString } from 'class-validator';
+import { IsIn, IsInt, IsNotEmpty, IsOptional, IsString, Min } from 'class-validator';
 import { StepType } from '../scenario-step.entity';
 
 export class UpdateScenarioStepDto {
+  @ApiPropertyOptional({ example: 0 })
+  @IsOptional()
+  @IsInt()
+  @Min(0)
+  order?: number;
+
   @ApiPropertyOptional({ enum: ['login', 'exec'] })
   @IsOptional()
   @IsIn(['login', 'exec'])