fix: photo import language + no-recipe-recognized handling (v0.29.0)

importFromPhoto() accepted a locale param but silently discarded it
(named _locale, never read) — now builds a language instruction the
same way generate-recipe.ts does for text generation.

The AI output schema had no way to signal "couldn't find a recipe in
this image" — generateObject would always fabricate a title/fields.
Added a `found` boolean the model sets to false in that case; the
route now returns 422 instead of creating a garbage recipe and
sending the user into the editor with it.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

apps/web/components/recipe/ai-generate-dialog.tsx

@@ -158,8 +158,10 @@ export function AiGenerateDialog({
         body: JSON.stringify({ imageBase64: photoBase64, mimeType: photoMime }),
       });
       if (!res.ok) {
-        let msg = t("photoError");
-        try { msg = ((await res.json()) as { error?: string }).error ?? msg; } catch { /* non-JSON body */ }
+        let msg = res.status === 422 ? tRecipe("photoNoRecipeFound") : t("photoError");
+        if (res.status !== 422) {
+          try { msg = ((await res.json()) as { error?: string }).error ?? msg; } catch { /* non-JSON body */ }
+        }
         toast.error(msg);
         return;
       }