Return 404 for nonexistent search components #11532

[jacobtylerwalls]

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Description of Change

Respond with a 404 view instead of an unhandled 500 exception for requests to the search_home route with a nonexistent search-view param.

Issues Solved

Closes #11532

Checklist

• I targeted one of these branches:
  • dev/8.0.x (under development): features, bugfixes not covered below
  • dev/7.6.x (main support): regressions, crashing bugs, security issues, major bugs in new features
  • dev/6.2.x (extended support): major security issues, data loss issues
• I added a changelog in arches/releases
• I submitted a PR to arches-docs (if appropriate)
• Unit tests pass locally with my changes
• I added tests that prove my fix is effective or that my feature works
• My test fails on the target branch

Ticket Background

• Sponsored by: Farallon
• Found by: @jacobtylerwalls

Further comments

We can target 8 instead if this doesn't qualify as a "major" bug in a new feature, but would be nice since the LTS was recent to avoid issuing 500s in people's server logs if we can.

[whatisgalen]

@jacobtylerwalls this seems like a good change on its face especially from the point of view of the backend. However with being more concise about the type of error code (404 vs 500) the http404 seems to bypass the error handling in search_results and the end user is no longer in Arches search but is now sort of stranded on whatever the 404 page is. I don't actually think that should be the UX because there's nothing to tell you what went wrong in a prod deployment. I also think that maybe the 404 should be reserved for something more like a non-existent url path as opposed to a query parameter that leads to a non-existent thing in the database. @apeters I think you likely have thoughts on this as well.

[apeters]

@whatisgalen to me this is really like submitting an incorrect route to Arches. You're asking for a base page layout that doesn't exist. I think throwing an http404 makes sense in that case.

[apeters]

I'll approve this once the merge conflicts are fixed