[Designer] Designer and schema don’t agree on casing of attribute values

Problem Description

Designer creates certain attributes with an upper-cased first letter, which then shows up in code view as not adhering to the JSON schema:

When the casing is corrected to match the schema, designer then no longer recognizes it:

Affected properties that I have seen so far: size, weight, color, horizontalAlignment, spacing. There might be others.

Card JSON

{
    "type": "AdaptiveCard",
    "body": [
        {
            "type": "TextBlock",
            "size": "Medium",
            "weight": "Bolder",
            "text": "${title}",
            "style": "heading",
            "wrap": true
        }
    ],
    "$schema": "http://adaptivecards.io/schemas/adaptive-card.json",
    "version": "1.6"
}

Reproduce the mismatch using the Card JSON in the issue, checking the Designer and the JSON schema for size, weight, color, horizontalAlignment, and spacing. Compare the casing accepted by each view, then verify that the affected properties use consistent casing and remain recognized by both the Designer and schema validation.