(cli): import is not using a custom qualifier

### Describe the bug

Similar to #29179, `cdk import` ignores qualifier set in the `cdk.json` context and tries to use defaults.

Which results in a failure.

Supplying the stack name fixes the problem, but it's not a scalable approach.

### Regression Issue

- [ ] Select this option if this issue appears to be a regression.

### Last Known Working CDK Version

2.171.0

### Expected Behavior

`cdk import` to respect the qualifier.

### Current Behavior

Does not respect the qualifier.

### Reproduction Steps

Use a custom qualifier.

Try to do an import with a large template.

Get an error:

> ❌ my-stack-name failed: Error: Template too large to deploy ("cdk bootstrap" is required)

### Possible Solution

_No response_

### Additional Information/Context

_No response_

### CDK CLI Version

2.171.0

### Framework Version

_No response_

### Node.js Version

22

### OS

macOs

### Language

TypeScript

### Language Version

_No response_

### Other information

_No response_

Start with the cdk import command and the custom qualifier in cdk.json context, reproducing the failure with a large template on CDK CLI 2.171.0. Done means import honors the custom qualifier without requiring the stack name and avoids the default-bootstrap/template-size error.

Written by the indexing model from the issue text.