Implement Polish translation (#6283)

* Initial polish translation sweep

* rewrite feeds page flavor text

* bring up to date with dev branch, revisit some strings

* redoing some more...

* bring up to date

* rm dead strings, try out a different phrasing for threaded mode str

prev translation was nonsensical - we're already calling threads "wątki". let's try "recursive tree" instead to describe what threaded mode does

* tweaks here and there

* more tweaks. sign translation file

TL note: trying a new space-saving translation for send via direct message, old one made the context menu stretch

* space-saving translations for profile tabs

* up to date

* tl latest changes

* some small fixes

* few more tweaks around profile editing strings

* i dislike gendered languages

* yet more tweaks

* Update dates.ts

* Review suggestions (1)

* tiny fixes

* Review suggestions (2)

* Review suggestions (3)

* Review suggestions (4)

* "Anuluj wyciszenie"

* A few new strings

* Remove dead strings again

* Review suggestions (5)

* te -> to

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Co-authored-by: Frudrax Cheng <i@cynosura.one>

src/locale/languages.ts

@@ -19,6 +19,7 @@ export enum AppLanguage {
   it = 'it',
   ja = 'ja',
   ko = 'ko',
+  pl = 'pl',
   pt_BR = 'pt-BR',
   ru = 'ru',
   th = 'th',
@@ -49,6 +50,7 @@ export const APP_LANGUAGES: AppLanguageConfig[] = [
   {code2: AppLanguage.it, name: 'Italiano – Italian'},
   {code2: AppLanguage.ja, name: '日本語 – Japanese'},
   {code2: AppLanguage.ko, name: '한국어 – Korean'},
+  {code2: AppLanguage.pl, name: 'Polski – Polish'},
   {code2: AppLanguage.pt_BR, name: 'Português (BR) – Portuguese (BR)'},
   {code2: AppLanguage.ru, name: 'Русский – Russian'},
   {code2: AppLanguage.th, name: 'ภาษาไทย – Thai'},