feat: Generation Page AI workflows + AI/Vector modules + exam session fixes

Generation Page (complete rebuild):
- Full production-parity exam generation wizard with 4 IELTS modules
- Reading: AI passage gen, 5 exercise types (MCQ, Fill, Write, T/F, Match)
- Listening: 4 section types, AI context gen, TTS audio gen (ElevenLabs)
- Writing: Task 1/2, AI instruction gen, word limits, marks
- Speaking: 3 parts, AI script gen, avatar video gen (7 avatars)
- Per-module config: timer, CEFR difficulty, access, approval, rubrics
- Exam submission workflow (draft/published)

Exam Structures:
- New encoach.exam.structure model + CRUD controller
- ExamStructuresPage wired to real API

AI Module (encoach_ai):
- OpenAI service, ElevenLabs TTS, AWS Polly, ELAI avatars
- AI settings model with Odoo config parameters
- 7 generation endpoints (passage, exercises, instructions, scripts, context)

Vector Module (encoach_vector):
- pgvector integration for RAG-based content search
- Embedding service with sentence-transformers

Exam Session Fixes:
- Fixed ExamSession.tsx field mapping (question_type→type, exam_title→title)
- Fixed submit payload to include attempt_id and answers
- Fixed normalizeType to handle null/undefined

Tested: 12/12 API tests passed, browser-verified with real OpenAI calls
Made-with: Cursor

backend/custom_addons/encoach_adaptive/controllers/adaptive.py

@@ -1,5 +1,6 @@
 import json
 import logging
+import math
 from odoo import http
 from odoo.http import request
 from odoo.addons.encoach_api.controllers.base import (
@@ -164,6 +165,44 @@ class EncoachAdaptiveController(http.Controller):
             _logger.exception('student signals failed')
             return _error_response(str(e), 500)
 
+    # ------------------------------------------------------------------
+    # GET /api/adaptive/student/<int:student_id>/ability
+    # ------------------------------------------------------------------
+    @http.route('/api/adaptive/student/<int:student_id>/ability', type='http',
+                auth='none', methods=['GET'], csrf=False)
+    @jwt_required
+    def student_ability(self, student_id, **kw):
+        try:
+            Event = request.env['encoach.adaptive.event'].sudo()
+            signals = Event.search([
+                ('student_id', '=', student_id),
+                ('event_type', '=', 'signal'),
+            ], order='created_at asc')
+
+            trajectory = []
+            for s in signals:
+                trajectory.append({
+                    'signal_name': s.signal_name or '',
+                    'value': s.signal_value,
+                    'timestamp': s.created_at,
+                })
+
+            values = [s.signal_value for s in signals if s.signal_value]
+            theta = sum(values) / len(values) if values else 0.0
+            sem = math.sqrt(sum((v - theta) ** 2 for v in values) / len(values)) if len(values) > 1 else 1.0
+
+            return _json_response({
+                'student_id': student_id,
+                'theta': round(theta, 3),
+                'sem': round(sem, 3),
+                'trajectory': trajectory,
+                'n_signals': len(trajectory),
+            })
+
+        except Exception as e:
+            _logger.exception('student ability failed')
+            return _error_response(str(e), 500)
+
     # ------------------------------------------------------------------
     # GET /api/adaptive/student/<int:student_id>/recommended-resources
     # ------------------------------------------------------------------