feat: typed script parameters with validation and icon-grid selector

- Add ScriptParameterConfig model (string, integer, float, boolean, select types)
- Server-side validation at both define-time and execute-time
- Parameters passed as SCRIPT_PARAM_* environment variables
- Web UI parameter editor in script create/edit dialog (add/remove/reorder)
- Icon-grid selector component (ported from wled-screen-controller)
- Replace audio device dropdown with icon-grid selector
- Replace callback event dropdown with icon-grid selector
- Localization for parameter UI (en, ru)

media_server/config.py

@@ -26,6 +26,26 @@ class CallbackConfig(BaseModel):
     shell: bool = Field(default=True, description="Run command in shell")
 
 
+class ScriptParameterConfig(BaseModel):
+    """Configuration for a script parameter."""
+
+    type: str = Field(
+        ...,
+        description="Parameter type: string, integer, float, boolean, select",
+        pattern=r"^(string|integer|float|boolean|select)$",
+    )
+    description: str = Field(default="", description="Parameter description")
+    required: bool = Field(default=False, description="Whether the parameter is required")
+    default: Optional[str | int | float | bool] = Field(
+        default=None, description="Default value if not provided"
+    )
+    min: Optional[float] = Field(default=None, description="Minimum value (numeric types only)")
+    max: Optional[float] = Field(default=None, description="Maximum value (numeric types only)")
+    options: Optional[list[str]] = Field(
+        default=None, description="Allowed values (select type only)"
+    )
+
+
 class ScriptConfig(BaseModel):
     """Configuration for a custom script."""
 
@@ -36,6 +56,9 @@ class ScriptConfig(BaseModel):
     timeout: int = Field(default=30, description="Execution timeout in seconds", ge=1, le=300)
     working_dir: Optional[str] = Field(default=None, description="Working directory")
     shell: bool = Field(default=True, description="Run command in shell")
+    parameters: dict[str, ScriptParameterConfig] = Field(
+        default_factory=dict, description="Named parameters with type and validation rules"
+    )
 
 
 class LinkConfig(BaseModel):