feat(fusion_accounting_bank_rec): 4-pass confidence scoring pipeline

Task 11 of Phase 1 Bank Reconciliation. Adds the brain that ranks
candidate journal-item matches for a bank statement line.

Pass 1 — SQL filter (done by caller's _fetch_candidates).
Pass 2 — Statistical scoring: weighted blend of amount-delta,
         partner pattern fit, and precedent similarity.
Pass 3 — Optional AI re-rank when an LLM provider is configured;
         gracefully no-ops when provider missing, prompt module not
         yet present (Task 20), or the JSON response is malformed.
Pass 4 — Persistence (handled by engine.suggest_matches).

Returns top-K ScoredCandidate dataclasses with per-feature scores
exposed for transparency and future learning.

7 new tests added; full module suite green (51 tests, 0 failures).

Made-with: Cursor

fusion_accounting_bank_rec/tests/__init__.py

@@ -4,3 +4,4 @@ from . import test_matching_strategies
 from . import test_ai_suggestion_lifecycle
 from . import test_precedent_lookup
 from . import test_pattern_extraction
+from . import test_confidence_scoring

fusion_accounting_bank_rec/tests/test_confidence_scoring.py

@@ -0,0 +1,102 @@
+from datetime import date, timedelta, datetime
+from odoo.tests.common import TransactionCase, tagged
+from odoo.addons.fusion_accounting_bank_rec.services.confidence_scoring import (
+    score_candidates, ScoredCandidate,
+)
+from odoo.addons.fusion_accounting_bank_rec.services.matching_strategies import Candidate
+
+
+@tagged('post_install', '-at_install')
+class TestConfidenceScoring(TransactionCase):
+
+    def setUp(self):
+        super().setUp()
+        self.partner = self.env['res.partner'].create({'name': 'Scoring Test Partner'})
+        self.company = self.env.company
+        self.currency = self.env.ref('base.CAD')
+
+        self.journal = self.env['account.journal'].create({
+            'name': 'Test Bank Scoring',
+            'type': 'bank',
+            'code': 'TBSC',
+        })
+        statement = self.env['account.bank.statement'].create({
+            'name': 'Test Statement',
+            'journal_id': self.journal.id,
+        })
+        self.line = self.env['account.bank.statement.line'].create({
+            'statement_id': statement.id,
+            'journal_id': self.journal.id,
+            'date': date.today(),
+            'payment_ref': 'RBC ETF DEP REF 4831',
+            'amount': 1847.50,
+            'partner_id': self.partner.id,
+        })
+
+    def _candidate(self, id_, amount, age_days=10):
+        return Candidate(id=id_, amount=amount, partner_id=self.partner.id, age_days=age_days)
+
+    def test_returns_empty_when_no_candidates(self):
+        result = score_candidates(self.env, statement_line=self.line, candidates=[], k=5)
+        self.assertEqual(result, [])
+
+    def test_returns_empty_when_no_statement_line(self):
+        result = score_candidates(self.env, statement_line=None,
+                                    candidates=[self._candidate(1, 100)], k=5)
+        self.assertEqual(result, [])
+
+    def test_amount_exact_dominates(self):
+        candidates = [
+            self._candidate(1, 1847.50),
+            self._candidate(2, 1800.00),
+        ]
+        result = score_candidates(self.env, statement_line=self.line, candidates=candidates, k=5,
+                                    use_ai=False)
+        self.assertEqual(len(result), 2)
+        self.assertEqual(result[0].candidate_id, 1)
+        self.assertGreater(result[0].confidence, result[1].confidence)
+        self.assertGreater(result[0].score_amount_match, 0.99)
+
+    def test_returns_top_k(self):
+        candidates = [self._candidate(i, 1847.50 - i) for i in range(10)]
+        result = score_candidates(self.env, statement_line=self.line, candidates=candidates, k=3,
+                                    use_ai=False)
+        self.assertEqual(len(result), 3)
+
+    def test_no_ai_provider_returns_statistical_only(self):
+        """When no AI provider config, score_ai_rerank stays at 0.0."""
+        self.env['ir.config_parameter'].sudo().search([
+            ('key', 'in', ['fusion_accounting.provider.bank_rec_suggest',
+                           'fusion_accounting.provider.default'])
+        ]).unlink()
+        candidates = [self._candidate(1, 1847.50)]
+        result = score_candidates(self.env, statement_line=self.line, candidates=candidates, k=5,
+                                    use_ai=True)
+        self.assertEqual(result[0].score_ai_rerank, 0.0)
+
+    def test_use_ai_false_skips_ai_rerank(self):
+        candidates = [self._candidate(1, 1847.50)]
+        result = score_candidates(self.env, statement_line=self.line, candidates=candidates, k=5,
+                                    use_ai=False)
+        self.assertEqual(result[0].score_ai_rerank, 0.0)
+
+    def test_pattern_match_boosts_confidence(self):
+        """When the partner has a matching pattern, confidence is higher than no-pattern case."""
+        self.env['fusion.reconcile.pattern'].create({
+            'company_id': self.company.id,
+            'partner_id': self.partner.id,
+            'reconcile_count': 10,
+            'pref_strategy': 'exact_amount',
+        })
+        candidates = [self._candidate(1, 1847.50)]
+        with_pattern = score_candidates(self.env, statement_line=self.line,
+                                          candidates=candidates, k=5, use_ai=False)
+
+        other_partner = self.env['res.partner'].create({'name': 'No Pattern Partner'})
+        self.line.write({'partner_id': other_partner.id})
+        other_candidates = [Candidate(id=1, amount=1847.50, partner_id=other_partner.id, age_days=10)]
+        without_pattern = score_candidates(self.env, statement_line=self.line,
+                                             candidates=other_candidates, k=5, use_ai=False)
+
+        self.assertGreater(with_pattern[0].score_partner_pattern,
+                            without_pattern[0].score_partner_pattern - 0.001)