Project Title Build Vendor Login, Onboarding & Lead Management System for Construction Platform (Custom Code) Project Overview I am building BuildSaathi, a construction and interiors lead-generation platform for India (Jaipur pilot). I need a custom, code-based system for: Vendor onboarding Vendor login & dashboard Lead management & assignment This is NOT a public directory and NOT a marketplace. Vendor profiles are visible only to the respective vendor and admin. I am not interested in no-code tools like Glide or Bubble for this phase. Core Requirements 1️⃣ Authentication & Roles Email/password authentication Roles: Admin Vendor Vendors must only access their own data Admin has full access Preferred: JWT / session-based auth Secure role-based access control 2️⃣ Vendor Onboarding Flow Vendor onboarding should be a form-based flow: Step 1: Select Vendor Type Professional Material Vendor If Professional: Category (Contractor, Architect, Interior Designer, Electrician, Plumber, etc.) Years of experience City Business name Optional description If Material Vendor: Material categories (Cement, Steel, Tiles, Hardware, etc.) Business name City Optional description Data should be stored cleanly and be editable later by the vendor. 3️⃣ Vendor Dashboard (Vendor-Only) After login, vendor should see: My Profile Edit business details Upload profile picture / logo Upload shop, office, warehouse, or project images Upload certificates (optional, no verification logic required) My Leads View only leads assigned to that vendor Read-only access to lead details Vendor should NOT: See other vendors See unassigned leads See customer contact details beyond what admin allows 4️⃣ Lead Management (Admin) Admin dashboard should allow: Create leads manually View all leads Assign leads to vendors Change lead status (New, Assigned, In Progress, Closed) View vendor profiles Tech Stack Preferences (Open to Suggestions) Preferred stack (but flexible if justified): Frontend: React / Next.js / plain HTML + JS Backend: Node.js / Express / NestJS Database: PostgreSQL / MySQL Auth: Custom or Supabase/Firebase Auth Hosting: Cloud-ready (Vercel, VPS, etc.) The system should be: Modular Scalable Easy to maintain What I Already Have Live Wix website (marketing site) Clear product flow Defined onboarding logic Pilot city: Jaipur (India) Deliverables Working codebase Vendor onboarding flow Vendor & admin dashboards Lead assignment system Basic deployment support Brief documentation