[State CosmosDB] Preserve property order

When reading an entry from a CosmosDB backed state store, properties are returned in seemingly random order, often shuffled differently on each fetch.

This breaks `System.Text.Json` polymorphism, as the `$type` (or other delimiter) **must** be the first property read in an object.

## Expected Behavior

The JSON should not be modified or altered, when read from the state store.

When the value:

```json
{
"$type": "some-type",
"value": "some-value"
}
```

Is stored in the state store, _get state_ should return:

```json
{
"$type": "some-type",
"value": "some-value"
}
```

## Actual Behavior
When the value:

```json
{
"$type": "some-type",
"value": "some-value"
}
```

Is stored in the state store, _get state_ will _randomly_ return either:

```json
{
"$type": "some-type",
"value": "some-value"
}
```
or
```json
{
"value": "some-value"
"$type": "some-type"
}
```

## Steps to Reproduce the Problem

1. Store JSON value in `state.azure.cosmosdb` state store
2. Read value from state store
3. Compare JSON property order

## Release Note

RELEASE NOTE: **FIX** CosmosDB state returns shuffled JSON

Start by locating the state.azure.cosmosdb component and trace its get-state read path. Reproduce the issue by storing the provided JSON and reading it repeatedly, then verify that the returned JSON preserves the original property order and that the component's tests cover this behavior.

Written by the indexing model from the issue text.