[FEATURE] Configure overwrite for symbolic targets

[quambene]

Is your feature request related to a problem? Please describe.

Often, the target file already exists on a system that was just set up. For example, ~/.bashrc already exists which requires dotter deploy --force. Though I would prefer not to apply force to all targets.

Describe the solution you'd like

For this reason, a forced overwrite should be configurable per target.

It's already possible to configure the type per target:

[bash.files]
bashrc = { target = "~/.bashrc", type = "symbolic" }

It should also be possible to overwrite the existing file, which could look like this:

[bash.files]
bashrc = { target = "~/.bashrc", type = "symbolic", overwrite = "force" }

An alternative configuration is:

[bash.files]
bashrc = { target = "~/.bashrc", type = "symbolic_overwrite" }

Describe alternatives you've considered

An alternative to achieve the same is to run dotter deploy twice. In particular:

1. Create all targets as symbolic links: dotter deploy
2. Now also replace existing targets which failed in the first step: dotter deploy --force

---

Happy to contribute if this feature makes sense to you.