feat: pentest onboarding — streaming, browser automation, reports, user cleanup (#16)

Complete pentest feature overhaul: SSE streaming, session-persistent browser tool (CDP), AES-256 credential encryption, auto-screenshots in reports, code-level remediation correlation, SAST triage chunking, context window optimization, test user cleanup (Keycloak/Auth0/Okta), wizard dropdowns, attack chain improvements, architecture docs with Mermaid diagrams.

Co-authored-by: Sharang Parnerkar <parnerkarsharang@gmail.com>
Reviewed-on: #16

docker-compose.yml

@@ -1,6 +1,6 @@
 services:
   mongo:
-    image: mongo:latest
+    image: mongo:7
     ports:
       - "27017:27017"
     environment: