chore: fork dsh-better-sidebar v0.18.0 as dsh-apes-sidebar v1.0.0

- Rename dsh-better-sidebar → dsh-apes-sidebar across 74 files (262 occurrences)
- Bump version 0.18.0 → 1.0.0 (package.json + dsh.plugin.json + SIDEBAR_SERVICE_VERSION)
- Add forkedFrom metadata to package.json (upstream pin: commit 9e1a034)
- Add fork notice banner to README.md (MIT attribution preserved)
- Keep original MIT copyright (c) 2026 dsh-external
- Full gate green: typecheck + build (6 bundles) + test (1241 passed / 9 skipped)

tests/e2e/toggle-layout.e2e.ts

@@ -51,7 +51,7 @@ interface FrameSample {
 test('bottom panel tracks the center column during the right-panel toggle transition (issue #315)', async ({ page }) => {
   await page.goto(PAGE_URL, { waitUntil: 'domcontentloaded' })
   await expect(page.locator('#root > *')).not.toHaveCount(0, { timeout: 90_000 })
-  const sidebar = page.locator('[data-dsh-better-sidebar]')
+  const sidebar = page.locator('[data-dsh-apes-sidebar]')
   await expect(sidebar).toBeAttached({ timeout: 90_000 })
 
   // Dismiss onboarding (same dance as the drag lane).