Better Resource management for sandbox

### Environment information

```plain text
npx ampx info
System:
OS: macOS 13.3.1
CPU: (8) arm64 Apple M1 Pro
Memory: 179.75 MB / 16.00 GB
Shell: /bin/zsh
Binaries:
Node: 18.17.1 - /usr/local/bin/node
Yarn: 1.22.19 - /opt/homebrew/bin/yarn
npm: 10.2.4 - /opt/homebrew/bin/npm
pnpm: undefined - undefined
NPM Packages:
@aws-amplify/backend: 1.0.0
@aws-amplify/backend-cli: 1.0.1
aws-amplify: 6.3.0
aws-cdk: 2.141.0
aws-cdk-lib: 2.138.0
typescript: 5.4.5
AWS environment variables:
AWS_SDK_LOAD_CONFIG = 1
AWS_STS_REGIONAL_ENDPOINTS = regional
AWS_NODEJS_CONNECTION_REUSE_ENABLED = 1
No CDK environment variables
```

### Description

would like a similar interface for sandbox like we have for deployed branches
eg. access to functions and resources

No files or tests are named. Start by locating the existing interface for accessing functions and resources in deployed branches, then trace the sandbox workflow and reproduce it with the listed npx ampx environment. Done means sandbox users have a comparable way to access its functions and resources, with the intended scope confirmed.

Written by the indexing model from the issue text.