Autocomplete tags in the preview panel

[Tyrannicodin]

Adds autocomplete to tags in the preview panel, for all tag fields.
You can now add tags through several methods:

1. Beginning to type a tag's name and
   a. Clicking enter to get the first tag that matches the text
   b. Using the arrow keys to select a tag from the autocomplete popup
   c. Clicking on a tag from the autocomplete popup
2. Clicking the plus button and using the previous tag modal.

Requires #481

[yedpodtrzitko]

I'll read through the code, but same thing as with #481 - please add some tests to verify the behaviour automatically and to prevent regressions in future. There are some existing tests for widgets in tests/qt, so you can use these as an inspiration. Thank you.

[Tyrannicodin]

Yep that's fine, I made this before I looked at that pr so can add some tests to both of them.

[yedpodtrzitko]

@CyanVoxel can you please enable the workflow to run on this PR? Thanks.

[yedpodtrzitko]

.

[yedpodtrzitko]

here's a bug:

Steps to reproduce:

• only Archived and Favorite tags exist
• type meow into the field to add new tag & press Enter

Expected behaviour:

• since no matching tag exists, no tag should be added

Current behaviour:

• tag Archived is added

[yedpodtrzitko]

Please add some tests for the widget, thanks.

[Tyrannicodin]

Added tests and fixed the bugs 👍

[yedpodtrzitko]

it looks good, beside the Enter behaviour on no-match. good job.

[Tyrannicodin]

Changes made

[yedpodtrzitko]

please fix the pipeline

[yedpodtrzitko]

it's quite misbehaving

Screen.Recording.2024-09-22.at.8.21.15.mov

[Tyrannicodin]

What. I've never seen it do that.
I'll look into it in the morning