feat: endpoint pratiche rendicontazione (lato beneficiario)

- 4 nuove tabelle: remission_practice, remission_invoice, remission_ula_employee, remission_document
  con cascade delete e FK
- 13 endpoint /api/remission-practices/*:
  GET /mine (lista pratiche user + applications CONTRACT_SIGNED ready_to_start)
  POST /start (avvia pratica da application_id, richiede schema PUBLISHED)
  GET /{id}, PUT /{id} (regime IVA + note)
  POST/DELETE /{id}/invoices
  POST/DELETE /{id}/ula-employees
  PUT/DELETE /{id}/documents/{doc_code}
  GET /{id}/gate-check (valida gate rules contro pratica, ritorna totali + checks)
  POST /{id}/submit (gate-check obbligatorio, status DRAFT -> SUBMITTED)
- 1 endpoint debug /api/debug/impersonate (sandbox-only, genera JWT per utente
  - necessario perche' /v1/user/login del BE Spring esclude ROLE_BENEFICIARY)
- Gate check calcola: totali per categoria, grand_total, max_remission = min(cap_pct*erogato, cap_abs),
  remission_due = min(grand_total, max_remission), applica iva_ordinario_imponibile_only

app/models.py

@@ -4,9 +4,10 @@ Schema: gepafin_rendic (stesso DB del BE Gepafin sandbox).
 """
 import uuid
 from datetime import datetime
-from sqlalchemy import Column, Integer, String, Text, DateTime, ForeignKey, UniqueConstraint
+from sqlalchemy import Column, Integer, String, Text, DateTime, ForeignKey, UniqueConstraint, Numeric, Boolean, Date
 from sqlalchemy.dialects.postgresql import UUID, JSONB
 from sqlalchemy.sql import func
+from sqlalchemy.orm import relationship
 from .db import Base
 
 
@@ -32,3 +33,111 @@ class CallRemissionSchema(Base):
     updated_at = Column(DateTime(timezone=True), nullable=False, server_default=func.now(), onupdate=func.now())
     published_at = Column(DateTime(timezone=True), nullable=True)
     published_by = Column(Integer, nullable=True)
+
+
+class RemissionPractice(Base):
+    """
+    Pratica di rendicontazione di un beneficiario per una specifica application in CONTRACT_SIGNED.
+    Uno schema_snapshot congelato alla creazione: se il superadmin modifica lo schema
+    del bando dopo, la pratica continua a usare la versione snapshot.
+    """
+    __tablename__ = "remission_practice"
+    __table_args__ = (
+        UniqueConstraint("application_id", name="uq_remission_practice_application"),
+        {"schema": "gepafin_rendic"},
+    )
+
+    id = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
+    call_id = Column(Integer, nullable=False)
+    application_id = Column(Integer, nullable=False, unique=True)
+    company_id = Column(Integer, nullable=False)
+    user_id = Column(Integer, nullable=False)  # beneficiario che compila
+
+    status = Column(String(32), nullable=False, default="DRAFT")
+    # DRAFT -> SUBMITTED -> UNDER_REVIEW -> APPROVED | REJECTED | AWAITING_AMENDMENT
+
+    schema_snapshot = Column(JSONB, nullable=False)  # copia schema al momento start
+    iva_regime = Column(String(32), nullable=True)  # ORDINARIO | FORFETTARIO | ESENTE
+    amount_erogato = Column(Numeric(14, 2), nullable=False)  # copiato da application.amount_accepted
+    notes_beneficiario = Column(Text, nullable=True)
+
+    created_at = Column(DateTime(timezone=True), nullable=False, server_default=func.now())
+    updated_at = Column(DateTime(timezone=True), nullable=False, server_default=func.now(), onupdate=func.now())
+    submitted_at = Column(DateTime(timezone=True), nullable=True)
+
+    # relazioni
+    invoices = relationship("RemissionInvoice", back_populates="practice", cascade="all, delete-orphan")
+    ula_employees = relationship("RemissionUlaEmployee", back_populates="practice", cascade="all, delete-orphan")
+    documents = relationship("RemissionDocument", back_populates="practice", cascade="all, delete-orphan")
+
+
+class RemissionInvoice(Base):
+    """Fattura rendicontata dentro una pratica, assegnata a una categoria."""
+    __tablename__ = "remission_invoice"
+    __table_args__ = ({"schema": "gepafin_rendic"},)
+
+    id = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
+    practice_id = Column(UUID(as_uuid=True),
+                         ForeignKey("gepafin_rendic.remission_practice.id", ondelete="CASCADE"),
+                         nullable=False)
+    category_code = Column(String(16), nullable=False)  # B1 / B2 / B3 / custom
+
+    invoice_number = Column(String(128), nullable=False)
+    invoice_date = Column(Date, nullable=False)
+    payment_date = Column(Date, nullable=False)
+    supplier_name = Column(String(255), nullable=False)
+    supplier_vat = Column(String(32), nullable=False)
+    description = Column(Text, nullable=False)
+    taxable = Column(Numeric(14, 2), nullable=False)  # imponibile
+    vat = Column(Numeric(14, 2), nullable=False, default=0)
+    total = Column(Numeric(14, 2), nullable=False)
+    pdf_filename = Column(String(512), nullable=True)  # per ora solo nome, upload vero dopo
+
+    created_at = Column(DateTime(timezone=True), nullable=False, server_default=func.now())
+
+    practice = relationship("RemissionPractice", back_populates="invoices")
+
+
+class RemissionUlaEmployee(Base):
+    """Dipendente conteggiato nel calcolo ULA."""
+    __tablename__ = "remission_ula_employee"
+    __table_args__ = ({"schema": "gepafin_rendic"},)
+
+    id = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
+    practice_id = Column(UUID(as_uuid=True),
+                         ForeignKey("gepafin_rendic.remission_practice.id", ondelete="CASCADE"),
+                         nullable=False)
+
+    codice_fiscale = Column(String(16), nullable=False)
+    full_name = Column(String(255), nullable=False)
+    contract_type = Column(String(64), nullable=False)  # T_IND / T_DET / APPR / ...
+    role_description = Column(String(255), nullable=True)
+    fte_pct = Column(Numeric(5, 4), nullable=False, default=1)  # 0..1
+    period_start_date = Column(Date, nullable=False)
+    period_end_date = Column(Date, nullable=False)
+
+    supporting_doc_type = Column(String(64), nullable=True)
+    supporting_doc_filename = Column(String(512), nullable=True)
+
+    created_at = Column(DateTime(timezone=True), nullable=False, server_default=func.now())
+
+    practice = relationship("RemissionPractice", back_populates="ula_employees")
+
+
+class RemissionDocument(Base):
+    """Documento associato alla pratica (DURC, visura, ecc.)."""
+    __tablename__ = "remission_document"
+    __table_args__ = ({"schema": "gepafin_rendic"},)
+
+    id = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
+    practice_id = Column(UUID(as_uuid=True),
+                         ForeignKey("gepafin_rendic.remission_practice.id", ondelete="CASCADE"),
+                         nullable=False)
+
+    doc_code = Column(String(64), nullable=False)  # DURC / VISURA_CAMERALE / ...
+    filename = Column(String(512), nullable=True)
+    uploaded_at = Column(DateTime(timezone=True), nullable=True)
+    expires_at = Column(Date, nullable=True)
+    notes = Column(Text, nullable=True)
+
+    practice = relationship("RemissionPractice", back_populates="documents")