feat(pagination): add generic typed pagination with ordering to all list endpoints

- add PaginationQueryDto<TOrderBy> generic with orderBy and orderDir fields
- add SessionOrderBy, EnvironmentOrderBy, ScenarioOrderBy type aliases
- update session, environment, scenario services and controllers to use typed pagination
- update MCP list_sessions, list_environments, list_scenarios tools to expose orderBy/orderDir
- update tests for all list endpoints to cover page, limit, ordering, and invalid param rejection

src/scenario/scenario.controller.ts

@@ -17,6 +17,7 @@ import { UpdateScenarioDto } from './dto/update-scenario.dto';
 import { CreateScenarioStepDto } from './dto/create-scenario-step.dto';
 import { UpdateScenarioStepDto } from './dto/update-scenario-step.dto';
 import { PaginationQueryDto } from './dto/pagination-query.dto';
+import { ScenarioOrderBy } from './scenario.service';
 import { RunsQueryDto } from './dto/runs-query.dto';
 
 @ApiTags('scenarios')
@@ -36,7 +37,7 @@ export class ScenarioController {
   @Get()
   @ApiOperation({ summary: 'List all scenarios (paginated)' })
   @ApiResponse({ status: 200 })
-  findAll(@Query() query: PaginationQueryDto) {
+  findAll(@Query() query: PaginationQueryDto<ScenarioOrderBy>) {
     return this.scenarioService.findAll(query);
   }