feat(v3): restructure project + add complete frontend

- Restructure: move backend from new_project/ to backend/
- Add full React/TypeScript frontend (37 pages, 17 services, 16 type defs, 11 query hooks)
- Add docs/ with SRS specs, user stories, and workflow documentation
- Update .gitignore for new directory layout

Workflows implemented:
  WF1 User Signup, WF2 Placement Test, WF3 Exam Configuration,
  WF4 General English Exam, WF5 Course Generation,
  WF6 Entity Student Onboarding, AI Course Generation,
  Adaptive Learning Engine UI, White-Label Branding, Score Release

Made-with: Cursor

custom_addons/encoach_signup/services/captcha_service.py

@@ -0,0 +1,33 @@
+import requests
+from odoo import api, SUPERUSER_ID
+
+
+class CaptchaService:
+
+    def __init__(self, env):
+        self.env = env
+
+    def verify(self, token):
+        """Verify CAPTCHA token against configured provider."""
+        ICP = self.env['ir.config_parameter'].sudo()
+        secret_key = ICP.get_param('encoach.captcha_secret_key', '')
+        provider = ICP.get_param('encoach.captcha_provider', 'recaptcha')
+
+        if provider == 'recaptcha':
+            url = 'https://www.google.com/recaptcha/api/siteverify'
+        elif provider == 'hcaptcha':
+            url = 'https://hcaptcha.com/siteverify'
+        elif provider == 'turnstile':
+            url = 'https://challenges.cloudflare.com/turnstile/v0/siteverify'
+        else:
+            return False
+
+        try:
+            resp = requests.post(url, data={
+                'secret': secret_key,
+                'response': token,
+            }, timeout=10)
+            result = resp.json()
+            return result.get('success', False)
+        except Exception:
+            return False