Update schema to use explicit property lists rather than the "bag of properties" (#323)

Author: jacobsimionato

packages/spikes/gulf_genkit_eval/GEMINI.md

@@ -4,6 +4,11 @@ This document outlines the validation rules that should be implemented in the `v
 
 Each message corresponds to one of the four message schemas: `stream_header.json`, `component_update.json`, `data_model_update.json`, or `begin_rendering.json`.
 
+## `StreamHeader` Message Rules
+
+*   **Required**: Must have a `version` property.
+*   No other properties are allowed.
+
 ## `ComponentUpdate` Message Rules
 
 ### 1. Component ID Integrity
@@ -13,39 +18,54 @@ Each message corresponds to one of the four message schemas: `stream_header.json
 
 ### 2. Component-Specific Property Rules
 
-For each component in the `components` array, the following rules apply based on its `type`:
+For each component in the `components` array, the following rules apply:
 
 *   **General**:
-    *   A component must have an `id` and a `type`.
-
-*   **Value Components** (`Heading`, `Text`, `Image`, `Video`, `AudioPlayer`, `TextField`, `CheckBox`, `DateTimeInput`, `MultipleChoice`, `Slider`):
+    *   A component must have an `id` and a `componentProperties` object.
+    *   The `componentProperties` object must contain exactly one key, which defines the component's type (e.g., "Heading", "Text").
+
+*   **Heading**:
+    *   **Required**: Must have a `text` property.
+*   **Text**:
+    *   **Required**: Must have a `text` property.
+*   **Image**:
+    *   **Required**: Must have a `url` property.
+*   **Video**:
+    *   **Required**: Must have a `url` property.
+*   **AudioPlayer**:
+    *   **Required**: Must have a `url` property.
+*   **TextField**:
+    *   **Required**: Must have a `label` property.
+*   **DateTimeInput**:
+    *   **Required**: Must have a `value` property.
+*   **MultipleChoice**:
+    *   **Required**: Must have a `selections` property.
+*   **Slider**:
     *   **Required**: Must have a `value` property.
-
 *   **Container Components** (`Row`, `Column`, `List`):
     *   **Required**: Must have a `children` property.
     *   The `children` object must contain *either* `explicitList` *or* `template`, but not both.
-
 *   **Card**:
     *   **Required**: Must have a `child` property.
-
 *   **Tabs**:
     *   **Required**: Must have a `tabItems` property, which must be an array.
     *   Each item in `tabItems` must have a `title` and a `child`.
-
 *   **Modal**:
     *   **Required**: Must have both `entryPointChild` and `contentChild` properties.
-
 *   **Button**:
     *   **Required**: Must have `label` and `action` properties.
-
 *   **CheckBox**:
     *   **Required**: Must have `label` and `value` properties.
+*   **Divider**:
+    *   No required properties.
 
 ## `DataModelUpdate` Message Rules
 
-*   **Path and Contents**: A `DataModelUpdate` message must have a `contents` property. The `path` property is optional.
+*   **Required**: A `DataModelUpdate` message must have a `contents` property.
+*   The `path` property is optional.
 *   If `path` is not present, the `contents` object will replace the entire data model.
 *   If `path` is present, the `contents` will be set at that location in the data model.
+*   No other properties besides `path` and `contents` are allowed.
 
 ## `BeginRendering` Message Rules