Add agents to aitools list output

[rclarey]

Changes

Update aitools list to report every supported coding agent (both text and --output json) with its detection status (whether the CLI binary and config directory were found) and databricks plugin installation status and version.

Why

This is needed to power integration with the VSCode extension in two places:

• agents list + detection is needed to prompt users for which agents to install tools for
• agents list + version is needed to show UI of what is installed

Tests

Added automated tests

[eng-dev-ecosystem-bot]

Integration test report

Commit: b90063a

Run: 29908086837

	Env	🟨​KNOWN	💚​RECOVERED	🙈​SKIP	✅​pass	🙈​skip	Time
💚​	aws linux		4	4	314	1055	9:30
💚​	aws windows		4	4	316	1053	7:56
💚​	azure linux		4	4	314	1054	9:26
💚​	azure windows		4	4	316	1052	6:30
🟨​	gcp linux	3	1	4	313	1056	11:00
🟨​	gcp windows	3	1	4	315	1054	11:31

8 interesting tests: 4 SKIP, 3 KNOWN, 1 RECOVERED

	Test Name	aws linux	aws windows	azure linux	azure windows	gcp linux	gcp windows
💚​	TestAccept	💚​R	💚​R	💚​R	💚​R	💚​R	💚​R
🙈​	TestAccept/bundle/invariant/no_drift	🙈​S	🙈​S	🙈​S	🙈​S	🙈​S	🙈​S
🙈​	TestAccept/bundle/resources/vector_search_endpoints/drift/recreated_same_name	🙈​S	🙈​S	🙈​S	🙈​S	🙈​S	🙈​S
🙈​	TestAccept/bundle/resources/vector_search_indexes/recreate/embedding_dimension	🙈​S	🙈​S	🙈​S	🙈​S	🙈​S	🙈​S
🙈​	TestAccept/ssh/connection	🙈​S	🙈​S	🙈​S	🙈​S	🙈​S	🙈​S
🟨​	TestFetchRepositoryInfoAPI_FromRepo	💚​R	💚​R	💚​R	💚​R	🟨​K	🟨​K
🟨​	TestFetchRepositoryInfoAPI_FromRepo/root	💚​R	💚​R	💚​R	💚​R	🟨​K	🟨​K
🟨​	TestFetchRepositoryInfoAPI_FromRepo/subdir	💚​R	💚​R	💚​R	💚​R	🟨​K	🟨​K

Top 5 slowest tests (at least 2 minutes):

duration	env	testname
6:20	aws windows	TestAccept
5:04	gcp windows	TestAccept
3:17	azure windows	TestAccept
2:38	gcp windows	TestImportDirDoesNotOverwrite
2:03	aws linux	TestAccept/bundle/deploy/mlops-stacks/DATABRICKS_BUNDLE_ENGINE=terraform

[github-actions]

Approval status: pending

/cmd/aitools/ - needs approval

Files: cmd/aitools/list.go, cmd/aitools/list_test.go
Suggested: @simonfaltum
Also eligible: @renaudhartert-db, @fjakobs, @Shridhad, @atilafassina, @keugenek, @igrekun, @pkosiec, @MarioCadenas, @pffigueiredo, @ditadi, @calvarjorge, @hectorcast-db, @parthban-db, @tanmay-db, @Divyansh-db, @tejaskochar-db, @mihaimitrea-db, @chrisst, @rauchy, @lennartkats-db

General files (require maintainer)

Files: .nextchanges/cli/aitools-list-agents.md
Based on git history:

• @simonfaltum -- recent work in cmd/aitools/

_{Any maintainer (@andrewnester, @anton-107, @denik, @pietern, @shreyas-goenka, @simonfaltum, @renaudhartert-db, @janniklasrose, @lennartkats-db) can approve all areas.
See OWNERS for ownership rules.}