refactor(scenario): remove step type and simplify scheduler to exec-only

- remove StepType, type column, and type field from step entity and DTOs
- remove executeLoginStep, executeSignStep, executeExecStep from scheduler
- inline exec logic directly in executeStepRun; all steps run execCode
- remove AuthService, EnvironmentService, runEnvironments from scheduler
- remove type selector from CreateStepPage and EditStepPage
- remove type badge column from ScenarioDetailPage
- fix useEffect dependency arrays in RunDetailPage (FINAL, id, runId, polling)
- fix duplicate /snippets proxy key in vite.config.ts
- remove unused escapeHtml export from hljs.ts

server/src/scenario/scenario.service.ts

@@ -1,4 +1,8 @@
-import { ConflictException, Injectable, NotFoundException } from "@nestjs/common";
+import {
+  ConflictException,
+  Injectable,
+  NotFoundException,
+} from "@nestjs/common";
 import { InjectRepository } from "@nestjs/typeorm";
 import { Like, Repository } from "typeorm";
 import { ScenarioEntity } from "./scenario.entity";
@@ -66,7 +70,11 @@ export class ScenarioService {
   async findOne(id: string): Promise<ScenarioEntity> {
     const scenario = await this.scenarioRepo.findOne({
       where: { id },
-      relations: ["steps", "scenarioCredentials", "scenarioCredentials.credential"],
+      relations: [
+        "steps",
+        "scenarioCredentials",
+        "scenarioCredentials.credential",
+      ],
       order: { steps: { order: "ASC" } },
     });
     if (!scenario) throw new NotFoundException(`Scenario ${id} not found`);
@@ -187,7 +195,9 @@ export class ScenarioService {
    * Builds a map of alias → parsed credential data for use in code execution.
    * Returns null values for credentials with no data.
    */
-  async buildCredentialMap(scenarioId: string): Promise<Record<string, unknown>> {
+  async buildCredentialMap(
+    scenarioId: string,
+  ): Promise<Record<string, unknown>> {
     const scs = await this.findScenarioCredentials(scenarioId);
     const map: Record<string, unknown> = {};
     for (const sc of scs) {
@@ -227,7 +237,9 @@ export class ScenarioService {
 
   async findAllRuns(
     query: RunsQueryDto,
-  ): Promise<PaginatedResult<ScenarioRunEntity & { scenario: ScenarioEntity }>> {
+  ): Promise<
+    PaginatedResult<ScenarioRunEntity & { scenario: ScenarioEntity }>
+  > {
     const page = query.page ?? 1;
     const limit = query.limit ?? 20;
     const where: Record<string, unknown> = {};