fix: address Qodo code review findings

- Add missing snapshot-differ.test.ts to npm test script
- Fix path traversal vulnerability in agent-mail.ts with message ID validation
- Fix readLastTouchedVersion to log errors instead of silently swallowing them
- Sanitize log statements to not leak full paths
- Add projectRoot validation to all API routes
- Fix activity persistence write race conditions with promise chaining

Co-authored-by: openhands <openhands@all-hands.dev>

src/app/api/activity/route.ts

@@ -1,9 +1,26 @@
 import { activityEventBus } from '../../../lib/realtime';
 
+function isValidProjectRoot(root: string): boolean {
+  try {
+    const resolved = require('path').resolve(root);
+    return require('path').isAbsolute(resolved);
+  } catch {
+    return false;
+  }
+}
+
 export async function GET(request: Request): Promise<Response> {
   const url = new URL(request.url);
-  const projectRoot = url.searchParams.get('projectRoot') || undefined;
+  const projectRootParam = url.searchParams.get('projectRoot');
+  
+  if (projectRootParam && !isValidProjectRoot(projectRootParam)) {
+    return NextResponse.json(
+      { error: 'Invalid projectRoot path' },
+      { status: 400 }
+    );
+  }
 
+  const projectRoot = projectRootParam || undefined;
   const history = activityEventBus.getHistory(projectRoot);
 
   return Response.json(history);

src/app/api/agents/[agentId]/stats/route.ts

@@ -1,15 +1,30 @@
 import { NextResponse } from 'next/server';
+import path from 'node:path';
 import { readIssuesFromDisk } from '../../../../../lib/read-issues';
 import { activityEventBus } from '../../../../../lib/realtime';
 import { getAgentMetrics } from '../../../../../lib/agent-sessions';
 
+function isValidProjectRoot(root: string): boolean {
+  try {
+    const resolved = path.resolve(root);
+    return path.isAbsolute(resolved);
+  } catch {
+    return false;
+  }
+}
+
 export async function GET(
   request: Request,
   { params }: { params: Promise<{ agentId: string }> }
 ): Promise<Response> {
   const { agentId } = await params;
   const url = new URL(request.url);
-  const projectRoot = url.searchParams.get('projectRoot') ?? process.cwd();
+  const projectRootParam = url.searchParams.get('projectRoot');
+  const projectRoot = projectRootParam ?? process.cwd();
+
+  if (projectRootParam && !isValidProjectRoot(projectRootParam)) {
+    return NextResponse.json({ ok: false, error: 'Invalid projectRoot path' }, { status: 400 });
+  }
 
   try {
     const issues = await readIssuesFromDisk({ projectRoot, preferBd: true });

src/app/api/beads/read/route.ts

@@ -1,10 +1,27 @@
 import { NextResponse } from 'next/server';
-
+import path from 'node:path';
 import { readIssuesFromDisk } from '../../../../lib/read-issues';
 
+function isValidProjectRoot(root: string): boolean {
+  try {
+    const resolved = path.resolve(root);
+    return path.isAbsolute(resolved);
+  } catch {
+    return false;
+  }
+}
+
 export async function GET(request: Request): Promise<Response> {
   const url = new URL(request.url);
-  const projectRoot = url.searchParams.get('projectRoot') ?? process.cwd();
+  const projectRootParam = url.searchParams.get('projectRoot');
+  const projectRoot = projectRootParam ?? process.cwd();
+
+  if (projectRootParam && !isValidProjectRoot(projectRootParam)) {
+    return NextResponse.json(
+      { ok: false, error: { classification: 'validation', message: 'Invalid projectRoot path' } },
+      { status: 400 }
+    );
+  }
 
   try {
     const issues = await readIssuesFromDisk({ projectRoot, preferBd: true });

src/app/api/events/route.ts

@@ -17,6 +17,8 @@ async function readLastTouchedVersion(filePath: string): Promise<number | null>
     if ((error as NodeJS.ErrnoException).code === 'ENOENT') {
       return null;
     }
+    // Log non-ENOENT errors but don't swallow them silently
+    console.error('[Events] Failed to read last-touched version:', error);
     return null;
   }
 }

src/app/api/sessions/route.ts

@@ -3,11 +3,30 @@ import { readIssuesFromDisk } from '../../../lib/read-issues';
 import { activityEventBus } from '../../../lib/realtime';
 import { buildSessionTaskFeed, getCommunicationSummary } from '../../../lib/agent-sessions';
 
+function isValidProjectRoot(root: string): boolean {
+  // Basic validation: path should not contain traversal patterns
+  // and should resolve to an absolute path
+  try {
+    const resolved = require('path').resolve(root);
+    return require('path').isAbsolute(resolved);
+  } catch {
+    return false;
+  }
+}
+
 export const dynamic = 'force-dynamic';
 
 export async function GET(request: Request): Promise<Response> {
   const url = new URL(request.url);
-  const projectRoot = url.searchParams.get('projectRoot') ?? process.cwd();
+  const projectRootParam = url.searchParams.get('projectRoot');
+  const projectRoot = projectRootParam ?? process.cwd();
+
+  if (projectRootParam && !isValidProjectRoot(projectRoot)) {
+    return NextResponse.json(
+      { ok: false, error: { classification: 'validation', message: 'Invalid projectRoot path' } },
+      { status: 400 }
+    );
+  }
 
   try {
     const issues = await readIssuesFromDisk({ projectRoot, preferBd: true });