Configure Existing AWS Resources like the JS SDK

### Before opening, please confirm:

- [X] I have [searched for duplicate or closed issues](https://github.com/aws-amplify/amplify-android/issues?q=is%3Aissue+) and [discussions](https://github.com/aws-amplify/amplify-android/discussions).

### Language and Async Model

Not applicable

### Amplify Categories

Not applicable

### Gradle script dependencies

```groovy
// Put output below this line

```

### Environment information

```
# Put output below this line

```

### Please include any relevant guides or documentation you're referencing

_No response_

### Describe the feature request

The current system to use existing AWS resources is very suboptimal, because the `amplifyconfiguration.json` file gets overwritten any time we pull or push local changes to the cloud.

I propose to adapt this to be similar to the [JS SDK](https://docs.amplify.aws/lib/storage/getting-started/q/platform/js/#configure-your-application) where manual configurations can be done in the app without touching the configuration file.

### Initialization steps (if applicable)

_No response_

### Code Snippet

```java
// Put your code below this line.

```

### amplifyconfiguration.json

_No response_

### GraphQL Schema

```graphql
// Put your schema below this line

```

### Additional information and screenshots

_No response_

Review how amplifyconfiguration.json is currently used and compare it with the linked JavaScript SDK configuration approach. Determine the Android API and configuration boundaries needed for manual AWS resource settings without overwriting the file; completion should support app-level configuration that remains intact across cloud pulls and pushes.

Written by the indexing model from the issue text.