Add initial version of the search extension

[aduffeck]

Description

This pr adds the new search extension which indexes files and directories and makes them searchable using the search service from within the web UI.

Types of changes

• Bug fix (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 change)
• Technical debt
• Tests only (no source changes)

Checklist:

• Code changes
• Unit tests added
• Acceptance tests added
• Documentation ticket raised:

[update-docs]

Thanks for opening this pull request! The maintainers of this repository would appreciate it if you would create a changelog item based on your changes.

[butonic]

file names are indexed and show up in search results on the API, the web ui/owncloudsdk still filters them though and it seems folder are not indexed, yet. still, the PoC works!

[ownclouders]

💥 Acceptance test Core-API-Tests-ocis-storage-1 failed. Further test are cancelled...

[butonic]

runsh: Total unexpected failed scenarios throughout the test run:
apiFavorites/favorites.feature:115
apiFavorites/favorites.feature:116
apiFavorites/favorites.feature:141
apiFavorites/favorites.feature:142
apiFavorites/favorites.feature:267
apiFavorites/favorites.feature:268

fail because the proxy would have to route REPORT requests to /remote.php/dav based on the body:

• reva ocdav implements favorites
• ocis webdav implements search

[butonic]

• use search to provide lookup for favorites?
• needs to add favorite to index
  • option 1: use a custom favorites manager
  • option 2: use events
  • option 3: add to expected failures for now

tracked in #1228

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
48 Code Smells

1.2% Coverage
7.9% Duplication