feat: Enhance currency handling and validation across scenarios

- Updated form template to prefill currency input with default value and added help text for clarity.
- Modified integration tests to assert more descriptive error messages for invalid currency codes.
- Introduced new tests for currency normalization and validation in various scenarios, including imports and exports.
- Added comprehensive tests for pricing calculations, ensuring defaults are respected and overrides function correctly.
- Implemented unit tests for pricing settings repository, ensuring CRUD operations and default settings are handled properly.
- Enhanced scenario pricing evaluation tests to validate currency handling and metadata defaults.
- Added simulation tests to ensure Monte Carlo runs are accurate and handle various distribution scenarios.

config/settings.py

@@ -7,6 +7,8 @@ from functools import lru_cache
 
 from typing import Optional
 
+from services.pricing import PricingMetadata
+
 from services.security import JWTSettings
 
 
@@ -56,6 +58,10 @@ class Settings:
     admin_password: str = "ChangeMe123!"
     admin_roles: tuple[str, ...] = ("admin",)
     admin_force_reset: bool = False
+    pricing_default_payable_pct: float = 100.0
+    pricing_default_currency: str | None = "USD"
+    pricing_moisture_threshold_pct: float = 8.0
+    pricing_moisture_penalty_per_pct: float = 0.0
 
     @classmethod
     def from_environment(cls) -> "Settings":
@@ -105,6 +111,18 @@ class Settings:
             admin_force_reset=cls._bool_from_env(
                 "CALMINER_SEED_FORCE", False
             ),
+            pricing_default_payable_pct=cls._float_from_env(
+                "CALMINER_PRICING_DEFAULT_PAYABLE_PCT", 100.0
+            ),
+            pricing_default_currency=cls._optional_str(
+                "CALMINER_PRICING_DEFAULT_CURRENCY", "USD"
+            ),
+            pricing_moisture_threshold_pct=cls._float_from_env(
+                "CALMINER_PRICING_MOISTURE_THRESHOLD_PCT", 8.0
+            ),
+            pricing_moisture_penalty_per_pct=cls._float_from_env(
+                "CALMINER_PRICING_MOISTURE_PENALTY_PER_PCT", 0.0
+            ),
         )
 
     @staticmethod
@@ -145,6 +163,23 @@ class Settings:
                 seen.add(role_name)
         return tuple(ordered)
 
+    @staticmethod
+    def _float_from_env(name: str, default: float) -> float:
+        raw_value = os.getenv(name)
+        if raw_value is None:
+            return default
+        try:
+            return float(raw_value)
+        except ValueError:
+            return default
+
+    @staticmethod
+    def _optional_str(name: str, default: str | None = None) -> str | None:
+        raw_value = os.getenv(name)
+        if raw_value is None or raw_value.strip() == "":
+            return default
+        return raw_value.strip()
+
     def jwt_settings(self) -> JWTSettings:
         """Build runtime JWT settings compatible with token helpers."""
 
@@ -180,6 +215,16 @@ class Settings:
             force_reset=self.admin_force_reset,
         )
 
+    def pricing_metadata(self) -> PricingMetadata:
+        """Build pricing metadata defaults."""
+
+        return PricingMetadata(
+            default_payable_pct=self.pricing_default_payable_pct,
+            default_currency=self.pricing_default_currency,
+            moisture_threshold_pct=self.pricing_moisture_threshold_pct,
+            moisture_penalty_per_pct=self.pricing_moisture_penalty_per_pct,
+        )
+
 
 @lru_cache(maxsize=1)
 def get_settings() -> Settings: