feat: initial backend codebase — EnCoach v3

Complete Odoo 19 backend with 25 custom addons:
- encoach_core: user/entity/role management
- encoach_api: REST API + JWT auth
- encoach_ai: OpenAI integration, AI settings, generation
- encoach_ai_course: AI-powered English & IELTS course generation
- encoach_exam_template/session: exam creation, structures, sessions
- encoach_scoring: AI auto-grading + manual approval
- encoach_vector: pgvector RAG integration
- encoach_adaptive: adaptive learning engine
- encoach_placement: placement testing
- encoach_taxonomy/resources: content taxonomy & resource management
- Plus 14 more modules for courses, branding, portal, etc.

Includes docs: user guide, generation report, developer workflow.

Made-with: Cursor

custom_addons/encoach_taxonomy/models/subject.py

@@ -0,0 +1,24 @@
+from odoo import models, fields
+
+
+class EncoachSubject(models.Model):
+    _name = 'encoach.subject'
+    _description = 'Taxonomy Subject'
+    _order = 'sequence, name'
+
+    name = fields.Char(required=True, index=True)
+    code = fields.Char(size=20, index=True)
+    description = fields.Text()
+    sequence = fields.Integer(default=10)
+    active = fields.Boolean(default=True)
+    domain_ids = fields.One2many('encoach.domain', 'subject_id', string='Domains')
+
+    def to_api_dict(self):
+        self.ensure_one()
+        return {
+            'id': self.id,
+            'name': self.name,
+            'code': self.code or '',
+            'description': self.description or '',
+            'active': self.active,
+        }