test(ratchet): lower the shell and rail baselines

sidebar-nav.tsx drops under 800 lines with its scroll region in a module
of its own, and AuthShell and SidebarNav are shorter.

src/__tests__/baselines/source-function-lines.json

@@ -1,7 +1,7 @@
 {
   "$comment": "Production functions over 200 lines, keyed \"file :: name\", and their length. Maintained by src/__tests__/source-size-ratchet.test.ts.",
   "count": 355,
-  "total": 114773,
+  "total": 114755,
   "entries": {
     "app/achievements/page.tsx :: AchievementsPage": 206,
     "app/api/admin/backups/upload/route.ts :: apiHandler(arg)": 314,
@@ -143,10 +143,10 @@
     "components/labs/lab-list.tsx :: LabList": 308,
     "components/labs/ocr-review-dialog.tsx :: OcrReviewDialog": 359,
     "components/labs/ocr-row-editor.tsx :: OcrRowEditor": 393,
-    "components/layout/auth-shell.tsx :: AuthShell": 520,
+    "components/layout/auth-shell.tsx :: AuthShell": 518,
     "components/layout/bottom-nav.tsx :: BottomNav": 262,
     "components/layout/capture-picker.tsx :: CapturePicker": 235,
-    "components/layout/sidebar-nav.tsx :: SidebarNav": 372,
+    "components/layout/sidebar-nav.tsx :: SidebarNav": 356,
     "components/layout/top-bar.tsx :: TopBar": 212,
     "components/links/entity-link-picker.tsx :: EntityLinkPicker": 392,
     "components/measurement-reminders/vorsorge-dashboard-card.tsx :: VorsorgeDashboardCard": 215,