feat: quality_tier CPAM (A/B/C) + requires_review + warnings catégorisés

- ControleCPAM enrichi : quality_tier, requires_review, quality_warnings
- _assess_quality_tier() : classification basée sur score adversarial + warnings
  - Tier C (requires_review) : score <4, code hors périmètre, >2 preuves non traçables
  - Tier B : score 4-6, warnings mineurs
  - Tier A : score >=7, 0 critique
- _format_response() : bandeau "REVUE MANUELLE REQUISE" pour tier C,
  sections CRITIQUES/MINEURS séparées
- Badge qualité dans le viewer CPAM (vert A / orange B / rouge C)
- 17 tests : tier A/B/C, bandeau, séparation warnings, backward compat

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/control/cpam_validation.py

@@ -300,10 +300,91 @@ def _build_correction_prompt(
     return original_prompt + correction_block
 
 
-def _format_response(parsed: dict, ref_warnings: list[str] | None = None) -> str:
+def _assess_quality_tier(
+    parsed: dict,
+    ref_warnings: list[str],
+    grounding_warnings: list[str],
+    code_warnings: list[str],
+    adversarial_result: dict | None,
+) -> tuple[str, bool, list[str]]:
+    """Évalue le tier qualité (A/B/C) et le flag requires_review.
+
+    Classification :
+    - Tier C (requires_review=True) :
+        score adversarial < 4 OU code_warnings > 0 OU grounding_warnings > 2
+    - Tier B :
+        score adversarial 4-6 OU ref_warnings > 0 OU grounding_warnings 1-2
+    - Tier A :
+        score adversarial >= 7, 0 warning critique, <= 1 warning mineur
+
+    Returns:
+        (tier, requires_review, categorized_warnings)
+    """
+    categorized: list[str] = []
+    score = adversarial_result.get("score_confiance", -1) if adversarial_result else -1
+    has_critical = False
+    minor_count = 0
+
+    # --- Warnings critiques ---
+    for w in code_warnings:
+        categorized.append(f"[CRITIQUE] {w}")
+        has_critical = True
+
+    if score != -1 and score <= 3:
+        categorized.append(f"[CRITIQUE] Score adversarial très bas : {score}/10")
+        has_critical = True
+
+    if len(grounding_warnings) > 2:
+        for w in grounding_warnings:
+            categorized.append(f"[CRITIQUE] {w}")
+        has_critical = True
+    elif grounding_warnings:
+        for w in grounding_warnings:
+            categorized.append(f"[MINEUR] {w}")
+            minor_count += 1
+
+    # --- Warnings mineurs ---
+    for w in ref_warnings:
+        categorized.append(f"[MINEUR] {w}")
+        minor_count += 1
+
+    if adversarial_result and not adversarial_result.get("coherent", True):
+        for e in adversarial_result.get("erreurs", []):
+            if isinstance(e, str) and e.strip():
+                categorized.append(f"[MINEUR] Incohérence : {e}")
+                minor_count += 1
+
+    if score != -1 and 4 <= score <= 6:
+        categorized.append(f"[MINEUR] Score adversarial moyen : {score}/10")
+        minor_count += 1
+
+    # --- Classification ---
+    if has_critical or (score != -1 and score < 4):
+        tier = "C"
+        requires_review = True
+    elif minor_count > 0 or (score != -1 and 4 <= score <= 6):
+        tier = "B"
+        requires_review = False
+    else:
+        tier = "A"
+        requires_review = False
+
+    return tier, requires_review, categorized
+
+
+def _format_response(
+    parsed: dict,
+    ref_warnings: list[str] | None = None,
+    quality_tier: str | None = None,
+    categorized_warnings: list[str] | None = None,
+) -> str:
     """Formate la réponse LLM en texte lisible."""
     sections = []
 
+    # Bandeau qualité si tier C
+    if quality_tier == "C":
+        sections.append("⚠ REVUE MANUELLE REQUISE (Qualité : C)")
+
     analyse = parsed.get("analyse_contestation")
     if analyse:
         sections.append(f"ANALYSE DE LA CONTESTATION\n{analyse}")
@@ -368,8 +449,20 @@ def _format_response(parsed: dict, ref_warnings: list[str] | None = None) -> str
     if conclusion:
         sections.append(f"CONCLUSION\n{conclusion}")
 
-    # Avertissements sur les références non vérifiables
-    if ref_warnings:
+    # Avertissements catégorisés (nouveau format)
+    if categorized_warnings:
+        critiques = [w for w in categorized_warnings if w.startswith("[CRITIQUE]")]
+        mineurs = [w for w in categorized_warnings if w.startswith("[MINEUR]")]
+        if critiques:
+            sections.append(
+                "AVERTISSEMENTS CRITIQUES\n" + "\n".join(f"- {w}" for w in critiques)
+            )
+        if mineurs:
+            sections.append(
+                "AVERTISSEMENTS MINEURS\n" + "\n".join(f"- {w}" for w in mineurs)
+            )
+    elif ref_warnings:
+        # Fallback ancien format
         warning_text = "\n".join(f"- {w}" for w in ref_warnings)
         sections.append(f"AVERTISSEMENT — REFERENCES NON VÉRIFIÉES\n{warning_text}")