Feature/lmstudio provider (#30)

* chore: just a plan update

* Add LM Studio as local AI provider (OpenAI-compatible, like Ollama)

* Convert WebP thumbnails to JPEG before image analysis for LM Studio compatibility

* Strengthen language enforcement in image analysis prompt for local models

* Use i18n localized prompts for image analysis instead of English instructions

* Add airplane mode (Flugmodus) with status bar toggle and offline model preferences

* Fix flightmode: persist model IDs, skip network when offline, airplane icon

* Auto-fallback to offline models in airplane mode for chat, title, and image analysis

* Auto-select first local model as offline fallback when no explicit offline model configured

* Block git fetch/pull/push and site upload in airplane mode

* fix: thumbnails optimized for AI

* fix: error handling in airplane mode

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Co-authored-by: hugo <hugoms@me.com>

src/renderer/App.tsx

@@ -520,9 +520,13 @@ const App: React.FC = () => {
             return;
           }
           await window.electronAPI?.publish.uploadSite(prefs);
-        } catch (error) {
+        } catch (error: any) {
           console.error('Site upload failed:', error);
-          showToast.error(tr('app.uploadSiteFailed'));
+          if (error?.message?.includes('Airplane mode')) {
+            useAppStore.getState().showErrorModal({ message: tr('app.uploadSiteOfflineMode') });
+          } else {
+            showToast.error(tr('app.uploadSiteFailed'));
+          }
         }
       }) || (() => {})
     );