Make "raw search" work across all fields

### Problem Statement

I want to quickly search across all fields in an exception - e.g. stack.function, error.type, etc etc etc. This could be because I'm not sure where the string might appear and want to be conservative, or it might be because I as a new user of Sentry don't know I have to (or need to!) search in specific fields.

Recent situation: I got notified about a new exception via our previous (pre-Sentry) exception tracking system. I wanted to find the corresponding exception in Sentry (and related exceptions). I go to the Sentry search box and add "nt_escape_unicode_path" on the end (no quotes), which is a key function name in the stacktrace. I get back four issues, each with a single hit/instance - but I'm expecting to see an exception with tens of thousands of hits. None of the stack traces look similar.

My first thought in this situation is, "well, I guess sentry is broken - either search isn't working or ingestion isn't working in this case".

Not a good look!

### Solution Brainstorm

It's unclear to me what "raw search" (i.e. just putting text at the end of the search field) is currently searching over - but I contend it ought to be searching over any text field / property on an issue.

That's the way literally every other product I've ever used works.

### Product Area

Issues