Fix/better new project name handling

[hugocaillard]

Description

Fix #1480

• Ask users if they want to continue if the directory already exists or already contains files (when using .
• Allow to include path in project name clarinet new path/to/project
• Sanitize project name (only allow alphanum, -, and _

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 15.42857% with 148 lines in your changes missing coverage. Please review.

Project coverage is 40.87%. Comparing base (05b268c) to head (52a8a56).

Files	Patch %	Lines
components/clarinet-cli/src/frontend/cli.rs	24.10%	85 Missing :warning:
components/clarinet-cli/src/generate/project.rs	0.00%	56 Missing :warning:
components/clarinet-cli/src/generate/mod.rs	0.00%	7 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1481 +/- ## ========================================== + Coverage 40.74% 40.87% +0.12% ========================================== Files 87 87 Lines 32386 32366 -20 ========================================== + Hits 13197 13228 +31 + Misses 19189 19138 -51 ```

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