feat(i18n): add Swedish support + include Slovak in auto-fill defaults

Two related changes to the translation infrastructure:

1. Add Swedish (sv) as a supported locale in both the CLI and Monitor
   translation systems. Inspired by PR #121, which arrived before the
   current auto-generated cache layout existed.

2. Include Slovak (sk) in the default auto-fill target set. Guardrail #1
   in build_i18n_messages.py never overwrites a key whose target value
   differs from EN, so Vaso73's curated Slovak strings stay intact —
   auto-translation only fills keys that are still on the English
   fallback. Trade-off accepted: sk users see decent machine translation
   for new keys immediately instead of raw English while human curation
   catches up, and Vaso73 keeps full ownership of the wording via
   follow-up PRs.

Changes:
- AppImage/lib/i18n/languages.ts: add "sv" to LanguageCode + register
  in SUPPORTED_LANGUAGES.
- AppImage/messages/sv/common.json: stub — will be filled by the i18n
  workflow on the local bootstrap.
- .github/scripts/build_translation_cache.py: add "sv" to
  DEFAULT_LANGUAGES.
- .github/scripts/build_i18n_messages.py: add "sk" and "sv" to
  DEFAULT_LANGUAGES; update comments to explain the sk decision.
- .github/workflows/build-i18n-messages.yml: default input includes
  sk + sv; comments updated to match.

.github/scripts/build_i18n_messages.py

@@ -12,9 +12,9 @@ Guardrails:
     are extracted before translation and restored afterwards, so the
     interpolation contract stays intact regardless of what the
     translation provider does with the surrounding text.
-  - `sk` is skipped by default; override with --languages es,de,fr,it,pt,sk
-    if you ever want to include it (which will only fill missing keys,
-    not overwrite the existing 3632).
+  - `sk` IS translated by default too. Guardrail #1 protects every key
+    Vaso73 has curated by hand; auto-translation only fills the keys
+    that are still on the English fallback in sk.
 
 Reuses the same translation providers as build_translation_cache.py so
 the CI environment (googletrans pinning, AppImage provider) stays
@@ -40,10 +40,14 @@ from build_translation_cache import (  # noqa: E402
 )
 
 
-# sk is human-curated (Vaso73); default set excludes it so a naive
-# workflow run cannot accidentally overwrite curated strings. Users can
-# still pass --languages ...,sk if they want auto-fill for missing keys.
-DEFAULT_LANGUAGES = ("es", "de", "fr", "it", "pt")
+# sk IS included in the default. Guardrail #1 (never overwrite a key
+# whose target value differs from EN) protects every string Vaso73 has
+# already curated by hand — auto-translation only ever touches keys
+# that are still on the English fallback in sk. Trade-off accepted:
+# users on sk see a decent auto-translation for new keys instead of raw
+# English while the human maintainer catches up, and Vaso73 keeps full
+# ownership of the wording via follow-up PRs.
+DEFAULT_LANGUAGES = ("es", "de", "fr", "it", "pt", "sk", "sv")
 DEFAULT_CONTEXT = "Context: Technical UI text for a Proxmox management dashboard. Translate:"
 
 # next-intl / ICU-style placeholders: {name}, {vmid}, {count}, {app_name}.
@@ -169,9 +173,9 @@ def build_arg_parser() -> argparse.ArgumentParser:
         "--languages",
         default=",".join(DEFAULT_LANGUAGES),
         help=(
-            "Comma-separated target locales. Default excludes sk "
-            "(human-curated by Vaso73). Adding sk here only fills "
-            "keys that are still identical to the English fallback."
+            "Comma-separated target locales. Includes sk by default; "
+            "guardrail #1 never overwrites keys whose sk value differs "
+            "from EN, so Vaso73's curated translations are safe."
         ),
     )
     parser.add_argument(

.github/scripts/build_translation_cache.py

@@ -28,7 +28,7 @@ from urllib.parse import quote
 from urllib.request import Request, urlopen
 
 
-DEFAULT_LANGUAGES = ("es", "fr", "de", "it", "pt", "sk")
+DEFAULT_LANGUAGES = ("es", "fr", "de", "it", "pt", "sk", "sv")
 DEFAULT_CONTEXT = "Context: Technical message for Proxmox and IT. Translate:"
 TRANSLATE_CALL_RE = re.compile(
     r"""translate\s+(?P<quote>["'])(?P<text>(?:\\.|(?! (?P=quote) ).)*?)(?P=quote)""",

.github/workflows/build-i18n-messages.yml

@@ -10,12 +10,11 @@ name: Build i18n messages
 #
 # Guardrails baked into build_i18n_messages.py:
 #   - Never overwrites a key whose target value differs from EN (i.e.
-#     already translated by a human).
+#     already translated by a human). This is what makes it safe to
+#     include sk in the default set: Vaso73's curated strings are
+#     protected end-to-end; auto only fills keys still on the EN
+#     fallback.
 #   - `{placeholder}` tokens are protected end-to-end.
-#   - `sk` is excluded from the default list — Vaso73's locale is
-#     human-curated and full. Add it back via workflow_dispatch inputs
-#     if you ever want auto-fill for the ~200 keys added post his last
-#     PR (only missing keys will be touched; existing ones are safe).
 #
 # Triggers:
 #   - push to develop touching AppImage/messages/en/common.json
@@ -35,8 +34,8 @@ on:
         type: boolean
         default: false
       languages:
-        description: 'Comma-separated locales. Default: es,de,fr,it,pt (sk skipped).'
-        default: 'es,de,fr,it,pt'
+        description: 'Comma-separated locales. Default: es,de,fr,it,pt,sk,sv (guardrail protects Vaso73 sk).'
+        default: 'es,de,fr,it,pt,sk,sv'
 
 # Prevent two runs from racing on the same branch and fighting over the
 # auto-commit. cancel-in-progress:false because a full first-run may take

AppImage/lib/i18n/languages.ts

@@ -1,7 +1,7 @@
 export const LANGUAGE_STORAGE_KEY = "proxmenux-ui-language"
 export const DEFAULT_LANGUAGE = "en"
 
-export type LanguageCode = "en" | "es" | "fr" | "de" | "it" | "pt" | "sk"
+export type LanguageCode = "en" | "es" | "fr" | "de" | "it" | "pt" | "sk" | "sv"
 
 export type LanguageStatus = "complete" | "partial" | "needs-translation"
 
@@ -20,6 +20,7 @@ export const SUPPORTED_LANGUAGES: SupportedLanguage[] = [
   { code: "de", englishName: "German", nativeName: "Deutsch", status: "needs-translation" },
   { code: "it", englishName: "Italian", nativeName: "Italiano", status: "needs-translation" },
   { code: "pt", englishName: "Portuguese", nativeName: "Português", status: "needs-translation" },
+  { code: "sv", englishName: "Swedish", nativeName: "Svenska", status: "needs-translation" },
 ]
 
 export function isSupportedLanguage(value: string | null | undefined): value is LanguageCode {

AppImage/messages/sv/common.json

@@ -0,0 +1,3 @@
+{
+  "_meta": "Community translation target. Copy keys from ../en/common.json and translate the values. Placeholders like {vmid} must stay unchanged."
+}