[feat] categories: add icons for remaining category tabs (#6759)

Icons are provided for the main categories known to us.

The distinction between CATEGORY_GROUPS and CATEGORY_NAMES is abandoned in favor
of the latter.

HINT: we need single-color icons; transparent background and the color must be
`currentColor` so that the icons can be used in light/dark themes.

The following SVGs from the ionicons had to be revised (use ``currentColor``).

- client/simple/src/svg/ionicons/logo-rss.svg
- client/simple/src/svg/ionicons/radio-outline.svg
- client/simple/src/svg/ionicons/color-palette-outline.svg

For the following categories, I did not find any usable icons in Ionicons; new
SVGs were created for these categories.

- onions: client/simple/src/svg/ionicons/tor-browser.svg
- lyrics: client/simple/src/svg/ionicons/song-lyric-music.svg [1]
- packages: client/simple/src/svg/ionicons/package_2.svg [1]

[1] Based on Google's Material icons: https://fonts.google.com/icons

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

client/simple/theme_icons.ts

@@ -39,14 +39,17 @@ const simple_icons: IconSet[] = [
       alert: "alert-outline.svg",
       appstore: "apps-outline.svg",
       book: "book-outline.svg",
+      camera: "camera-outline.svg",
       close: "close-outline.svg",
       download: "download-outline.svg",
       "ellipsis-vertical": "ellipsis-vertical-outline.svg",
       "file-tray-full": "file-tray-full-outline.svg",
+      "file-tray-stacked": "file-tray-stacked-outline.svg",
       film: "film-outline.svg",
       globe: "globe-outline.svg",
       heart: "heart-outline.svg",
       image: "image-outline.svg",
+      language: "language-outline.svg",
       layers: "layers-outline.svg",
       leecher: "arrow-down.svg",
       location: "location-outline.svg",
@@ -58,13 +61,14 @@ const simple_icons: IconSet[] = [
       "navigate-up": "chevron-up-outline.svg",
       people: "people-outline.svg",
       play: "play-outline.svg",
-      radio: "radio-outline.svg",
+      rainy: "rainy-outline.svg",
       save: "save-outline.svg",
       school: "school-outline.svg",
       search: "search-outline.svg",
       seeder: "swap-vertical.svg",
       settings: "settings-outline.svg",
-      tv: "tv-outline.svg"
+      tv: "tv-outline.svg",
+      videocam: "videocam-outline.svg"
     },
     svgo_opts: sxng_icon_opts
   },
@@ -75,7 +79,13 @@ const simple_icons: IconSet[] = [
     base: resolve(HERE, "src/svg/ionicons"),
     set: {
       "information-circle": "information-circle-outline.svg",
-      newspaper: "newspaper-outline.svg"
+      lyrics: "song-lyric-music.svg",
+      newspaper: "newspaper-outline.svg",
+      palette: "color-palette-outline.svg",
+      package: "package_2.svg",
+      radio: "radio-outline.svg",
+      rss: "logo-rss.svg",
+      tor: "tor-browser.svg"
     },
     svgo_opts: sxng_icon_opts
   }