[Task] Create Stronghold (Snapshot)

## Description
- Create blank Snapshot at predefined path (return autogenerated PW)
- Fail if file exists

## Motivation
Describe the motivation for the feature to be developed.

## Resources
Link to any resources relevant for the task such as issues, PRs, reference implementations, or specifications.

## To-do list
Create a task-specific to-do list. Please link PRs that match the TODO list item behind the item after it has been submitted.

- [ ] Item one
- [ ] Item two
- [ ] Item three

## Change checklist
Add an `x` to the boxes that are relevant to your changes, and delete any items that are not.

- [ ] The feature or fix is implemented in Rust and across all bindings whereas possible.
- [ ] The feature or fix has sufficient testing coverage
- [ ] All tests and examples build and run locally as expected
- [ ] Every piece of code has been document according to the documentation guidelines.
- [ ] If conceptual documentation (mdbook) and examples highlighting the feature exist, they are properly updated.
- [ ] If the feature is not currently documented, a documentation task Issue has been opened to address this.

Start by locating the existing Stronghold and Snapshot creation entry points in the repository, then inspect how paths and autogenerated passwords are handled. Implement the blank Snapshot behavior at the predefined path, reject an existing file, and verify the behavior with the relevant tests or add coverage if none exists.

Written by the indexing model from the issue text.