Commandline parsing to get basic information about the app

[zjeffer]

Implements #215

> ./build/notes --help
Usage: ./build/notes [options]
Notes is a simple note-taking application.

Options:
  -h, --help     Displays help on commandline options.
  --help-all     Displays help, including generic Qt options.
  -v, --version  Displays version information.
  --count        Count the number of notes
  --trash-count  Count the number of notes in the trash
  --list-notes   List all notes

> ./build/notes --version
Notes 2.3.1

Creating a draft PR to get initial review and more ideas on what to add to the parser.
I haven't yet implemented the count, trash-count and list-notes options, because I'm not sure how we should best handle those. It would require setting up the DBManager in main.cpp, I guess. We could also just merge without those 3 options, to at least provide a --version argument.

[guihkx]

I really like this!

I can't think of any other command line switches we could add at the moment, but I like the ones you came up with.

For the --version switch ,I'd follow what most command line apps seem to output on Linux, which would be simply APP_NAME APP_VERSION (like you've showed in your post, but the code seems to display it differently?).

I'd also add the Qt version there (build version + runtime version), similarly to what we already do in the about window, e.g.:

$ ./notes --version
Notes 2.3.1
Qt 6.8.1 (built with Qt 6.8.0)

I like showing both Qt versions because since we unfortunately rely on private Qt headers, having mismatched build/runtime versions can be a source of problems sometimes...

[zjeffer]

I think we should also change the CMakeLists file to add the git commit to the app version, only in case of a manual compile (not releases). Otherwise we won't see which commit a user built from.

[guihkx]

That should be doable, yeah.

We actually do provide that info, but only if we build with -DGIT_REVISION=ON, which is turned off by default.

We could check if the current commit is tagged and prefixed with v, and then set GIT_REVISION=ON automatically if it's not - unless the user specifically turns it off in the command line switches.