docs: DX and performance improvements in API reference (#9430)

- Improve scroll behavior between active sections
- Improve lag when clicking on a sidebar item
- Refactor internal working of the `SidebarProvider` to find active items faster.
- Use Next.js's `useRouter` hook for changing the hash (since they added the option to disable scroll)
- Change `isBrowser` from a hook to a provider since it's widely used across applications.
- Other general improvements and fixes.

Closes DOCS-952

www/apps/api-reference/providers/index.tsx

@@ -2,9 +2,6 @@
 
 import {
   AnalyticsProvider,
-  ColorModeProvider,
-  MobileProvider,
-  ModalProvider,
   PageLoadingProvider,
   ScrollControllerProvider,
   SiteConfigProvider,
@@ -24,21 +21,15 @@ const Providers = ({ children }: ProvidersProps) => {
     <AnalyticsProvider writeKey={process.env.NEXT_PUBLIC_SEGMENT_API_KEY}>
       <SiteConfigProvider config={config}>
         <PageLoadingProvider>
-          <ModalProvider>
-            <ColorModeProvider>
-              <BaseSpecsProvider>
-                <ScrollControllerProvider scrollableSelector="#main">
-                  <SidebarProvider>
-                    <MainNavProvider>
-                      <SearchProvider>
-                        <MobileProvider>{children}</MobileProvider>
-                      </SearchProvider>
-                    </MainNavProvider>
-                  </SidebarProvider>
-                </ScrollControllerProvider>
-              </BaseSpecsProvider>
-            </ColorModeProvider>
-          </ModalProvider>
+          <BaseSpecsProvider>
+            <ScrollControllerProvider scrollableSelector="#main">
+              <SidebarProvider>
+                <MainNavProvider>
+                  <SearchProvider>{children}</SearchProvider>
+                </MainNavProvider>
+              </SidebarProvider>
+            </ScrollControllerProvider>
+          </BaseSpecsProvider>
         </PageLoadingProvider>
       </SiteConfigProvider>
     </AnalyticsProvider>