chore(deps): make Qt backend optional (#350)

* chore(deps): make Qt backend optional

TODO:
- [ ] Add relevant entry in CHANGELOG
- [ ] Update install documentation
- [ ] Make sure `manim-slides convert` can run without any Qt backend
- [ ] Make sure test suite works (partially) without any Qt backend
- [ ] Make sure we can import `manim_slides` without any Qt backend

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* chore(deps): some fixes but wip

* chore(docs): update

* chore(deps): support PyQt6

* chore(deps): make Qt backend optional

TODO:
- [ ] Add relevant entry in CHANGELOG
- [ ] Update install documentation
- [ ] Make sure `manim-slides convert` can run without any Qt backend
- [ ] Make sure test suite works (partially) without any Qt backend
- [ ] Make sure we can import `manim_slides` without any Qt backend

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* chore(deps): some fixes but wip

* chore(docs): update

* chore(deps): support PyQt6

* fix(deps): ci and docs

* fix(lib): missing package

* chore(ci): does it work?

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* chore(test): skip failing

* chore(docs): update

* chore(docs): update

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* fix(docs): typo

* fix(test): quit instead of shutdown

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

manim_slides/convert.py

@@ -648,14 +648,16 @@ def show_template_option(function: Callable[..., Any]) -> Callable[..., Any]:
     "config_options",
     multiple=True,
     callback=validate_config_option,
-    help="Configuration options passed to the converter. E.g., pass `-cslide_number=true` to display slide numbers.",
+    help="Configuration options passed to the converter. "
+    "E.g., pass ``-cslide_number=true`` to display slide numbers.",
 )
 @click.option(
     "--use-template",
     "template",
     metavar="FILE",
     type=click.Path(exists=True, dir_okay=False, path_type=Path),
-    help="Use the template given by FILE instead of default one. To echo the default template, use `--show-template`.",
+    help="Use the template given by FILE instead of default one. "
+    "To echo the default template, use ``--show-template``.",
 )
 @show_template_option
 @show_config_options