Move API endpoints under /api/configure/content/ to /api/content/

Pull out /api/configure/content API endpoints into /api/content to
allow for more logical organization of API path hierarchy

This should make the url more succinct and API request intent more
understandable by using existing HTTP method semantics along with the
path.

The /configure URL path segment was either
- redundant (e.g POST /configure/notion) or
- incorrect (e.g GET /configure/files)

Some example of naming improvements:
- GET /configure/types -> GET /content/types
- GET /configure/files -> GET /content/files
- DELETE /configure/files -> DELETE /content/files

This should also align, merge better the the content indexing API
triggered via PUT, PATCH /content

Refactor Flow
1. Rename /api/configure/types -> /api/content/types
2. Rename /api/configure -> /api
3. Move /api/content to api_content from under api_config

src/interface/desktop/search.html

@@ -212,7 +212,7 @@
             const headers = { 'Authorization': `Bearer ${khojToken}` };
 
             // Populate type dropdown field with enabled content types only
-            fetch(`${hostURL}/api/configure/types`, { headers })
+            fetch(`${hostURL}/api/content/types`, { headers })
                 .then(response => response.json())
                 .then(enabled_types => {
                     // Show warning if no content types are enabled