Post title performs search

It would be nice if users are pointed to other questions when they are posting a question to prevent duplicates. This can be implemented as a search using the post title/summary that users provide.

Required changes:

• Move post title to above the post, such that the user starts with a summary
• On input (but with some minor delay, we shouldn't spam the server too much), perform search (more fuzzy than normal search?)
• Show recommended questions to check before posting (inline, overlay?). When clicked, these should open in a new tab.

Initially, we should probably make this feature work with normal search but create a separate method for it. Then afterwards we can tune the search parameters to better fit this particular type of search.

EDIT: I see GitLab also has the same for issues, perhaps can be used for inspiration: