Add Project Meta-issue

@eleanorjboyd is already working on this.

Since May 9, 2025.

## Project Summary
One of the core functionalities of the python environments extension is project management. A `project` (in the context of this extension) will be defined as: "a single or group of python files which have a environment connected to them". Projects are created by a`PythonProjectCreator` which implements a `create` function that will return a `PythonProject`.

Here is the creators we plan to have as built-ins in the extension:
| Creator | Description | `QuickCreate` | MVP? | Issue |
| --- | --- | --- | --- | --- |
| Add Existing Project | Allow user to select file/folder within workspace | No | Yes | - |
| Auto-Find Project | Projects collected in workspace by finding `pyproject.toml` files | Yes? | Yes | #398 |
| Python Package | Create new Python Package | Yes | Yes | #392 |
| Python Script with PEP 723 | Create single script with env defined by PEP 723 format | Yes | Yes | #393 |
| Django | New Django project | Yes | No | #394 |
| FastAPI | Create new FastAPI project | Yes | No | #396 |
| Flask | Create new Flask project | Yes | No | #397 |

## Outstanding Work

### Todos and Status for Built in `PythonProjectCreator`
- [x] Add Existing Project
- [x] #398
- [x] #392
- [x] #393
- [ ] #394
- [ ] #396
- [ ] #397

### Copilot Integration
Additionally, build in projects will be linked up with copilot to provide better support for these project types by copilot during the "new" creation flow.
- [x] https://github.com/microsoft/vscode-python-environments/issues/286

### Bug Fixes
- [ ] https://github.com/microsoft/vscode-python-environments/issues/272
- [x] https://github.com/microsoft/vscode-python-environments/issues/179
- [x] https://github.com/microsoft/vscode-python-environments/issues/399
- [x] https://github.com/microsoft/vscode-python-environments/issues/410

### references:
- original issue on "new projects": https://github.com/microsoft/vscode-python-environments/issues/191
- over-arching issue on MVP: https://github.com/microsoft/vscode-python-environments/issues/190
- this repo needs to be added to with scenarios for use and testing: https://github.com/eleanorjboyd/python-envs-scenarios