feat(review): inline file uploader instead of redirect home

When a user lands on Review without an upload, show a file uploader
on the page itself and auto-run the analyzer once a file is picked,
rather than bouncing them to the home page with a "Back to home"
button.

Auto-analyze is the right default here: the user is already on the
Review page, so they've implicitly committed to a scan. Stashing the
bytes in the same session-state keys the home page uses keeps the
rest of the flow (encoding picker, gate, tool pages) unchanged.

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

tests/gui/test_workflows.py

@@ -156,16 +156,24 @@ class TestPipelineRunnerWorkflow:
 # ---------------------------------------------------------------------------
 
 class TestReviewWorkflow:
-    """The Review page is the gate-fixer. Without an upload it shows a
-    'go back to home' message. With an upload it runs the analyzer and
-    shows findings."""
+    """The Review page is the gate-fixer. Without an upload it shows
+    its own file uploader so the user can start the flow from this
+    page directly. With an upload it runs the analyzer and shows
+    findings."""
 
-    def test_no_upload_shows_back_to_home(self, app_factory):
+    def test_no_upload_shows_inline_uploader(self, app_factory):
         app = app_factory("0_Review")
         app.run()
         text = collected_text(app)
-        # Page shows ``No file uploaded`` + ``Back to home``.
-        assert "No file uploaded" in text or "uploaded" in text.lower()
+        # Page should invite the user to upload, not redirect home.
+        assert "Upload" in text or "Choose a file" in text, (
+            f"Review page should expose an inline uploader; got:\n{text[:400]}"
+        )
+        # The 'Back to home' button is gone — the page is self-contained now.
+        labels = [b.label for b in app.button]
+        assert not any("Back to home" in lbl for lbl in labels), (
+            f"Back-to-home button should be removed; got buttons: {labels}"
+        )
 
     def test_with_upload_shows_review_content(
         self, app_factory, small_csv_bytes,