chore(home): remove "Export report" button

The disabled "Export report" placeholder is gone — it wasn't tied to
a real feature and was just noise in the action bar. Action bar is
back to two buttons (Run analysis · Clear results) on a 1:1:4
column split. ``upload.export_report`` keys removed from en + es
i18n packs.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/gui/_home.py

@@ -414,9 +414,8 @@ def _home_page() -> None:
 
     pending = [name for name in home_uploads if name not in findings_by_file]
 
-    # Action bar — Run / Export report (disabled, coming soon) /
-    # Clear results, matching the mockup §action-bar.
-    col_run, col_export, col_clear, _ = st.columns([1, 1, 1, 3])
+    # Action bar — Run analysis / Clear results.
+    col_run, col_clear, _ = st.columns([1, 1, 4])
     with col_run:
         run_clicked = st.button(
             t("upload.run_button"),
@@ -425,14 +424,6 @@ def _home_page() -> None:
             disabled=not pending,
             width="stretch",
         )
-    with col_export:
-        st.button(
-            t("upload.export_report"),
-            key="home_export_report",
-            disabled=True,
-            help="Coming soon",
-            width="stretch",
-        )
     with col_clear:
         clear_clicked = st.button(
             t("upload.clear_results"),