feat(import): add import-only option for recipes without downloading missing LoRAs

Add dual-button design in recipe import flow:
- Details step: [Import Recipe Only] [Import & Download]
- Location step: [Back] [Import & Download] (removed redundant Import Only)

Changes:
- templates/components/import_modal.html: Add secondary button for import-only
- static/js/managers/ImportManager.js: Add saveRecipeOnlyFromDetails() method
- static/js/managers/import/RecipeDataManager.js: Update button state management
- static/js/managers/import/DownloadManager.js: Support skipDownload flag
- locales/*.json: Complete all translation TODOs

Closes #868

locales/en.json

@@ -645,6 +645,8 @@
                 "root": "Root",
                 "browseFolders": "Browse Folders:",
                 "downloadAndSaveRecipe": "Download & Save Recipe",
+                "importRecipeOnly": "Import Recipe Only",
+                "importAndDownload": "Import & Download",
                 "downloadMissingLoras": "Download Missing LoRAs",
                 "saveRecipe": "Save Recipe",
                 "loraCountInfo": "({existing}/{total} in library)",
@@ -1495,6 +1497,7 @@
             "processingError": "Processing error: {message}",
             "folderBrowserError": "Error loading folder browser: {message}",
             "recipeSaveFailed": "Failed to save recipe: {error}",
+            "recipeSaved": "Recipe saved successfully",
             "importFailed": "Import failed: {message}",
             "folderTreeFailed": "Failed to load folder tree",
             "folderTreeError": "Error loading folder tree",