Implement the new designed interface for fingerprint enrollment, so that the
dialog is now based on a stack of views:
- A list of devices to choose (shown only if multiple are available)
- A gallery of enrolled prints available where manage them
- An enrollment progress view when enrolling a new finger
Move part of the logic into a new FingerprintManager (to manage gdbus proxies
generated via gdbus-codegen) that is created when configuring the current
user and that tracks the devices states, while move most of the UI into a new
CcFingerprintDialog that does all the operations in async way.
Due to fprintd lack of APIs, there are few features missing, compared to
the final design (none is a regression):
- Identify the finger when the enroll dialog is visible
- Delete a single fingerprint
- Highlight the finger when the sensor is touched during enrollment
- Add customized labels to fingerprints
- Devices hotpluging
However most of the code has been written considering these, and so they could
be easily implemented in future re-iterations once newer APIs are defined for
such bits.
Closes https://gitlab.gnome.org/Teams/Design/settings-mockups/-/issues/18
