refactor: media types rework, dynamically load preview renderers (#1498)

* feat!: establish new MediaType system

* further additions and changes

* begin making renderers classes, improve text thumbnails

* continue renderer work

* convert most remaining thumbnail renderers to classes

* feat: dynamically load preview renderers

* refactor: use individual ext registration, continued progress

* refactor: finish converting old types to new registration system

* chore: alphabetize lists

* fix: only use search context for searches

* refactor: remove legacy filetype equivalent usages

* feat: add aliases for type groups, used in search

* refactor: use new MediaTypes system in archive renderers

* fix: add missing types

* refactor: remove last uses of legacy media type system

* refactor: move media type search context init to new file

* fix: fix import formatting, add missing aliases

* chore: remove leftover logging

* chore: small tweaks and comments

* refactor: wrap filetype init in function, call in driver

* docs: add and update docstrings

* fix: use all intended fallback icons for each media type

* fix: fix misc issues

* tests: add test cases for media types

* refactor: rename register_all to register_types

* refactor: wrap preview renderer type registrations in methods

REUSE.toml

@@ -55,3 +55,14 @@ path = [
 ]
 SPDX-FileCopyrightText = "(c) github:google/material-design-icons Contributors"
 SPDX-License-Identifier = "Apache-2.0"
+
+[[annotations]]
+path = ["src/tagstudio/resources/qt/fonts/Oxanium-Bold.ttf"]
+SPDX-FileCopyrightText = "(c) 2019 The Oxanium Project Authors (https://github.com/sevmeyer/oxanium)"
+SPDX-License-Identifier = "OFL-1.1"
+
+
+[[annotations]]
+path = ["src/tagstudio/resources/fonts/JetBrainsMono/**"]
+SPDX-FileCopyrightText = "(c) 2020 The JetBrains Mono Project Authors (https://github.com/JetBrains/JetBrainsMono)"
+SPDX-License-Identifier = "OFL-1.1"