feat(5.18): corpus k-NN exemple etichetate + seed real Haiku (17181 op)

Seed app/data/operatii-etichetate.json regenerat cu subagenti Haiku pe TOATE
cele 17181 operatii distincte (ordine frecventa, 100%), inlocuind seed-ul Groq
(3758). Validare Haiku vs Groq pe 157 op etichetate: la dezacorduri Haiku corect
~22/30, Groq ~0. Haiku prinde gunoiul ratat de Groq (ITP, chirie anvelope, nume
piese fara actiune): NUL 2200 (12.8%) vs ~7.6% Groq; adaptare electronica OE-7
(nu OE-5), placute frana uzura OE-1 (nu OE-F avarie).

US-001..006: prefiltru NUL determinist, etichetator offline, generator seed,
seeder mapping_suggestions (in init_db, gated seed_operatii_enabled), embeddings
indexeaza corpus etichetat, enrich NUL+kNN. Distributie seed: OE-1 80.1%, NUL
12.8%, OE-2 3.5%, restul rar (OE-4/3/7/8/R/I/5, AITLV, R-ODO).

config: seed_operatii_enabled=True + embeddings_enabled=True implicit (SILVER
populat + sugestii semantice; ambele suggestion-only, dezactivabile prin env).

Suita: 1387 passed, 1 deselected (live).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tests/test_prefiltru_nul.py

@@ -0,0 +1,72 @@
+"""US-001 (PRD 5.18) — pre-filtru determinist non-operatii (NUL).
+
+Masuratoarea k-NN (memorie test-precizie-knn-embeddings) arata recall NUL doar 64%:
+gunoiul evident (ITP, plata, discount, nr. inmatriculare, tractare) scapa ca OE-1.
+Un pre-filtru determinist il marcheaza NUL INAINTE de k-NN.
+
+Garantie non-negociabila (AC): ZERO fals-pozitiv pe operatii reale. Regulile
+text/regex au fost calibrate pe `docs/operatii-service/*.csv` (vezi sesiunea de
+implementare): triggerele ambigue (TRACTARE, NR INMATRICULARE/placuta) sunt
+ECRANATE de un context de piesa/operatie (D/R, CARLIG, CAPAC, INLOCUIT...).
+"""
+
+from __future__ import annotations
+
+from app.mapping import prefiltru_nul
+
+
+def test_itp_e_nul():
+    assert prefiltru_nul("13 X ITP") is True
+    assert prefiltru_nul("11XITP") is True          # glue fara spatii
+    assert prefiltru_nul("ITP") is True
+    assert prefiltru_nul("2 X ITP") is True
+
+
+def test_plata_discount_nul():
+    assert prefiltru_nul("DISCOUNT FIDELITATE 10%") is True
+    assert prefiltru_nul("REDUCERE COMERCIALA") is True
+    assert prefiltru_nul("ACHITAT DE CONF.URBAN") is True
+    assert prefiltru_nul("PLATA AVANS") is True
+    assert prefiltru_nul("TAXA DE MEDIU") is True
+
+
+def test_nr_inmatriculare_nul():
+    assert prefiltru_nul("NR INMATRICULARE") is True
+    assert prefiltru_nul("NUMAR INMATRICULARE") is True
+    assert prefiltru_nul("B 123 ABC") is True       # pattern placuta standalone
+    assert prefiltru_nul("CT 44 MKY") is True
+
+
+def test_tractare_serviciu_nul():
+    # Serviciul de tractare (rmorca) = non-operatie de service.
+    assert prefiltru_nul("TRACTARE CTA-SLOBOZIA") is True
+    assert prefiltru_nul("TRACTARE 100 KM") is True
+
+
+def test_operatie_reala_nu_e_nul():
+    # Punctul critic: trigger ambiguu intr-un context de piesa reala -> NU e NUL.
+    assert prefiltru_nul("INLOCUIT PLACUTE FRANA") is False
+    assert prefiltru_nul("D/R CARLIG TRACTARE") is False        # carlig = piesa, nu serviciu
+    assert prefiltru_nul("D/R CAPAC TRACTARE BARA SPATE") is False
+    assert prefiltru_nul("D/R NR INMATRICULARE") is False       # suport placuta = piesa
+    assert prefiltru_nul("D/R ELECTROMOTOR CT 44 MKY") is False  # placuta lipita la o operatie reala
+
+
+def test_zero_fals_pozitiv_pe_set_operatii_reale():
+    """AC: zero fals-pozitiv pe un set de 20 operatii reale (din docs/operatii-service)."""
+    reale = [
+        "REVIZIE", "SCHIMB ULEI MOTOR", "INLOCUIT PLACUTE FRANA FATA",
+        "D/R BARA FATA", "VOPSIT USA DR FATA", "INLOCUIT FILTRU AER",
+        "AERISIT INSTALATIE FRANA", "INLOCUIT AMORTIZOR SPATE", "ABSORBANT SOC BARA SPATE",
+        "INLOCUIT CUREA DISTRIBUTIE", "REGLAT FARURI", "INLOCUIT BUJII",
+        "REPARAT ARIPA FATA DR", "INLOCUIT DISCURI FRANA", "GRESAT PLANETARA",
+        "INLOCUIT RULMENT ROATA", "MONTAT ANVELOPE", "INLOCUIT BATERIE",
+        "DIAGNOZA COMPUTERIZATA", "INLOCUIT CONTACT PORNIRE",
+    ]
+    for op in reale:
+        assert prefiltru_nul(op) is False, f"fals-pozitiv pe operatie reala: {op!r}"
+
+
+def test_input_gol_nu_e_nul():
+    assert prefiltru_nul("") is False
+    assert prefiltru_nul(None) is False  # type: ignore[arg-type]