Rewrite class-based theme provider and toggle.

next-themes still defaults to dark with no system follow. Clerk theme wrapper stays inherited.

tests/test_periscope_frontend_theme_rewrite.py

@@ -0,0 +1,37 @@
+"""next-themes wrapper and toggle live under periscope/src."""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[1]
+SRC = ROOT / "periscope" / "src" / "frontend" / "src"
+
+
+def test_theme_modules_are_src():
+    for rel in (
+        "components/theme/theme-provider.tsx",
+        "components/theme/theme-toggle.tsx",
+    ):
+        text = (SRC / rel).read_text(encoding="utf-8")
+        assert "Native Periscope overlay" not in text[:400]
+
+
+def test_theme_provider_contract():
+    text = (SRC / "components/theme/theme-provider.tsx").read_text(encoding="utf-8")
+    assert "export function ThemeProvider" in text
+    assert 'attribute="class"' in text
+    assert 'defaultTheme="dark"' in text
+    assert "enableSystem={false}" in text
+    assert "disableTransitionOnChange" in text
+    clerk = SRC / "components/theme/clerk-theme-provider.tsx"
+    assert not clerk.exists()
+
+
+def test_theme_toggle_contract():
+    text = (SRC / "components/theme/theme-toggle.tsx").read_text(encoding="utf-8")
+    assert "export function ThemeToggle" in text
+    assert 'aria-label="Toggle theme"' in text
+    assert "resolvedTheme" in text
+    assert 'className="hidden h-4 w-4 dark:block"' in text
+    assert 'className="h-4 w-4 dark:hidden"' in text