feat(mcp): add file tools for scenarios and runs

- expose scenario file upload, listing, and content retrieval over MCP\n- expose run artifact listing and content retrieval with end-to-end coverage

server/src/scenario/scenario.service.ts

@@ -5,6 +5,7 @@ import {
   NotFoundException,
 } from "@nestjs/common";
 import { InjectRepository } from "@nestjs/typeorm";
+import * as fs from "fs/promises";
 import * as path from "path";
 import { Like, Repository } from "typeorm";
 import {
@@ -768,6 +769,47 @@ export class ScenarioService {
     res.sendFile(fullPath);
   }
 
+  /**
+   * Get scenario file content as a buffer (for MCP use).
+   * Returns metadata plus raw bytes without streaming to Response.
+   */
+  async getScenarioFileContentAsBuffer(
+    scenarioId: string,
+    fileId: string,
+  ): Promise<{ file: { id: string; name: string; mimeType: string; size: number; sha256: string; expiresAt: Date | null; createdAt: Date }; contentBuffer: Buffer }> {
+    // Verify scenario exists
+    await this.findOne(scenarioId);
+
+    // Check if file is linked to this scenario
+    const link = await this.scenarioFileRepo.findOne({
+      where: { scenarioId, fileId },
+      relations: ["file"],
+    });
+
+    if (!link) {
+      throw new NotFoundException(`File ${fileId} not found in scenario ${scenarioId}`);
+    }
+
+    const file = link.file;
+    const fullPath = path.resolve(this.fileStorageService.getAbsolutePath(file.filePath));
+
+    // Read file content as buffer
+    const contentBuffer = await fs.readFile(fullPath);
+
+    return {
+      file: {
+        id: file.id,
+        name: file.originalName,
+        mimeType: file.mimeType,
+        size: file.size,
+        sha256: file.sha256,
+        expiresAt: file.expiresAt,
+        createdAt: file.createdAt,
+      },
+      contentBuffer,
+    };
+  }
+
   async listRunFiles(
     scenarioId: string,
     runId: string,
@@ -833,4 +875,50 @@ export class ScenarioService {
 
     res.sendFile(fullPath);
   }
+
+  /**
+   * Get run artifact file content as a buffer (for MCP use).
+   * Returns metadata plus raw bytes without streaming to Response.
+   */
+  async getRunFileContentAsBuffer(
+    scenarioId: string,
+    runId: string,
+    fileId: string,
+  ): Promise<{ file: { id: string; name: string; mimeType: string; size: number; sha256: string; expiresAt: Date | null; createdAt: Date }; contentBuffer: Buffer }> {
+    // Verify scenario and run exist
+    await this.findOne(scenarioId);
+    const run = await this.runRepo.findOneBy({ id: runId, scenarioId });
+    if (!run) {
+      throw new NotFoundException(`Run ${runId} not found in scenario ${scenarioId}`);
+    }
+
+    // Check if file is linked to this run
+    const link = await this.scenarioRunFileRepo.findOne({
+      where: { runId, fileId },
+      relations: ["file"],
+    });
+
+    if (!link) {
+      throw new NotFoundException(`File ${fileId} not found in run ${runId}`);
+    }
+
+    const file = link.file;
+    const fullPath = path.resolve(this.fileStorageService.getAbsolutePath(file.filePath));
+
+    // Read file content as buffer
+    const contentBuffer = await fs.readFile(fullPath);
+
+    return {
+      file: {
+        id: file.id,
+        name: file.originalName,
+        mimeType: file.mimeType,
+        size: file.size,
+        sha256: file.sha256,
+        expiresAt: file.expiresAt,
+        createdAt: file.createdAt,
+      },
+      contentBuffer,
+    };
+  }
 }