fix: add client-side form validation to login and signup pages

[Ananya-CM]

Summary

Added real-time client-side validation to Login
and Signup pages using Zod schemas. Previously
users had to wait for server round-trips to see
errors for obviously invalid inputs.

Changes Made

frontend/app/login/page.tsx

• Added emailError and passwordError states
• Added validateEmail() using Zod email schema
• Added validatePassword() using Zod min(8) schema
• Email and password inputs now validate on onBlur
• Inline red error messages shown under each field
• Login button disabled until both fields pass
  validation (isFormValid check)

frontend/app/signup/page.tsx

• Added emailError, usernameError,
  passwordStrength states
• validateEmailField() uses existing
  signupSchema.shape.email from auth.ts
• validateUsernameField() uses existing
  signupSchema.shape.username from auth.ts
• Username and email inputs validate on onBlur
• Added real-time password strength indicator
  (Weak / Medium / Strong) with colored bars
• Inline red error messages shown under fields

Before

• No inline validation — user had to submit
  form to see errors
• No real-time feedback while typing
• Unnecessary API calls for invalid inputs

After

• ✅ Inline errors appear on field blur
• ✅ Login button disabled for invalid inputs
• ✅ Password strength bar (red/yellow/green)
• ✅ Uses existing Zod schemas from auth.ts

Screenshots

Files Changed

• frontend/app/login/page.tsx
• frontend/app/signup/page.tsx

Issue

Closes #99

nsoc26

[vercel]

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[github-actions]

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Project	Deployment	Actions	Updated (UTC)
flow-forge	Error		Jun 11, 2026 5:59pm

[Shriii19]

@Ananya-CM it have the deployment error so it ASAP.