refactor(session): auto-create named browser sessions

- create and register named browser sessions on open/exec when missing

- align scenario step DTO/entity/service by removing sessionName usage

- update MCP scenario-step schemas to use optional title fields

server/src/browser/browser.service.ts

@@ -9,8 +9,10 @@ import type { BrowserContext } from "playwright";
 import { Readability } from "@mozilla/readability";
 import { JSDOM } from "jsdom";
 import { SessionContextService } from "../session/session-context.service";
+import { SessionService } from "../session/session.service";
 import { CodeExecutorService } from "../code-executor/code-executor.service";
 import type { ExecResult } from "../code-executor/code-executor.service";
+import type { Cookie } from "playwright";
 
 export type { ExecResult } from "../code-executor/code-executor.service";
 
@@ -26,9 +28,54 @@ export class BrowserService {
 
   constructor(
     private readonly sessionContextService: SessionContextService,
+    private readonly sessionService: SessionService,
     private readonly codeExecutor: CodeExecutorService,
   ) {}
 
+  private parseCookies(raw: string | null | undefined): Cookie[] {
+    if (!raw) return [];
+    try {
+      const parsed = JSON.parse(raw) as unknown;
+      return Array.isArray(parsed) ? (parsed as Cookie[]) : [];
+    } catch {
+      return [];
+    }
+  }
+
+  private async getOrCreateNamedHandle(sessionName: string) {
+    try {
+      return await this.sessionContextService.getHandle(sessionName);
+    } catch {
+      this.logger.log(
+        `[${sessionName}] creating session context automatically`,
+      );
+
+      const browser = await chromium.launch({
+        headless: true,
+        executablePath: process.env.PLAYWRIGHT_CHROMIUM_EXECUTABLE_PATH,
+      });
+      const context = await browser.newContext();
+      const page = await context.newPage();
+
+      const existing = await this.sessionService.findBySessionName(sessionName);
+      const cookies = this.parseCookies(existing?.cookies);
+      if (cookies.length > 0) {
+        await context.addCookies(cookies);
+      }
+
+      this.sessionContextService.register(sessionName, browser, context, page);
+
+      await this.sessionService.upsert(
+        sessionName,
+        existing?.token ?? `auto:${sessionName}`,
+        await context.cookies(),
+        {},
+      );
+
+      return { browser, context, page };
+    }
+  }
+
   private rethrow(err: unknown, label: string, operation: string): never {
     if (err instanceof HttpException) {
       throw err;
@@ -90,8 +137,7 @@ export class BrowserService {
     this.logger.log(`[${label}] open: ${url}`);
 
     if (sessionName) {
-      const { context } =
-        await this.sessionContextService.getHandle(sessionName);
+      const { context } = await this.getOrCreateNamedHandle(sessionName);
       try {
         return await this.extractContent(context, url, readerMode, selector);
       } catch (err) {
@@ -123,7 +169,7 @@ export class BrowserService {
 
     if (sessionName) {
       const { page, context } =
-        await this.sessionContextService.getHandle(sessionName);
+        await this.getOrCreateNamedHandle(sessionName);
       this.logger.log(`[${label}] exec: using persistent context`);
       try {
         if (url) {

server/src/browser/dto/exec.dto.ts

@@ -4,7 +4,7 @@ import { IsOptional, IsString, IsUrl } from "class-validator";
 export class ExecDto {
   @ApiPropertyOptional({
     description:
-      "Session name previously created by POST /login. If omitted, executes without a stored session.",
+      "Optional named browser session. If it does not exist yet, it is created automatically.",
     example: "test-session-1",
   })
   @IsOptional()

server/src/browser/dto/open.dto.ts

@@ -4,7 +4,7 @@ import { IsBoolean, IsOptional, IsString, IsUrl } from "class-validator";
 export class OpenDto {
   @ApiPropertyOptional({
     description:
-      "Session name previously created by POST /login. If omitted, opens the URL without a stored session.",
+      "Optional named browser session. If it does not exist yet, it is created automatically.",
     example: "test-session-1",
   })
   @IsOptional()