Group results based on the file they belong to

Currently, irrespective of a file the results belong, they're being shown all at once. It'd look like mess when we have results for say 20 different files or even more and each file having 10 source ranges. Imagine, user will have to scroll all the way down to go through all the files' results.
Now we can do two things to avoid this:
1. Display only file names in result tab. Clicking on the file names would display all the results for corresponding file. Clicking on another file would close the results for previous one and open for the current file. Can be done with simple toggle.
2. Use pagination in case when number of files are large.

IMO 2nd option seems sustainable

cc @AbdealiJK @sils1297

Start by reviewing the result-tab implementation and how results from multiple files are currently presented. Before coding, clarify whether file toggles or pagination is required; done should mean results are grouped by file and users can navigate among files without scrolling through every result.

Written by the indexing model from the issue text.