codeintel: Make lack of indexers actionable to users
Created by: efritz
This effort is attached to #33795 (closed). This PR differentiates the unavailable cases into unsupported (wth are we looking at here?), and search-based available, but no precise indexer is. The latter case is actionable.
The user is now presented with a button that will record their request for support of a particular language. If this user has already requested that particular language, then a canned 'your request has been noted' message. This data is stored in a new Postgres table with a unique user_id/language_id pairing. Counts of requests by language id are sent via pings regular with on-prem update checks.
Blocked by https://github.com/sourcegraph/analytics/pull/412. Telemetry concerns pulled out into https://github.com/sourcegraph/sourcegraph/pull/34469. Merging this should not harm pings.
Test plan
Additional unit tests.
App preview:
Check out the client app preview documentation to learn more.