Fix type annotations for requires_value and when_value support

- validate.py: condition_label is Optional[str] (None for when_set)
- definitions.py: add annotations to inner _validate_condition closure
- docs_gen.py: use generic Dict/List types for _format_requires_value
  and _format_condition

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

Author: sbryngelson

toolchain/mfc/params/definitions.py

@@ -408,7 +408,7 @@ def _validate_dependency(param_name: str, dependency: Dict[str, Any]) -> None:
             )
         )
 
-    def _validate_condition(cond_label, condition):
+    def _validate_condition(cond_label: str, condition: Any) -> None:
         """Validate a condition dict (shared by when_true, when_set, when_value entries)."""
         if not isinstance(condition, dict):
             raise ValueError(

toolchain/mfc/params/generators/docs_gen.py

@@ -126,7 +126,7 @@ def _format_constraints(param) -> str:
     return ", ".join(parts)
 
 
-def _format_requires_value(rv: dict) -> str:
+def _format_requires_value(rv: Dict[str, list]) -> str:
     """Format a requires_value dict with human-readable labels."""
     items = []
     for param, vals in rv.items():
@@ -136,7 +136,7 @@ def _format_requires_value(rv: dict) -> str:
     return ", ".join(items)
 
 
-def _format_condition(trigger: str, condition: dict) -> list:
+def _format_condition(trigger: str, condition: Dict[str, Any]) -> List[str]:
     """Format a single condition dict into a list of description strings."""
     parts = []
     if "requires" in condition:

toolchain/mfc/params/validate.py

@@ -27,7 +27,7 @@
     3. Physics validation (via case_validator.py)
 """
 
-from typing import Dict, Any, List, Tuple
+from typing import Dict, Any, List, Optional, Tuple
 from .registry import REGISTRY
 from .errors import (
     dependency_error,
@@ -99,7 +99,7 @@ def validate_constraints(params: Dict[str, Any]) -> List[str]:
 def _check_condition(  # pylint: disable=too-many-arguments
     name: str,
     condition: Dict[str, Any],
-    condition_label: str,
+    condition_label: Optional[str],
     params: Dict[str, Any],
     errors: List[str],
     warnings: List[str],