internal: Add support for 'sensitive' JSON tag for bundle config fields

[andrewnester]

Changes

Add support for 'sensitive' JSON tag for bundle config fields

Why

This allows us to mark certain fields (for example, secrets.value) as sensitive and let CLI handle masking it in command outputs.

Used in #5861

Tests

Added unit tests. Will be tests end to end with unit tests with UC secrets

[github-actions]

Approval status: pending

/bundle/ - needs approval

Files: bundle/config/mask.go, bundle/config/mask_test.go
Suggested: @pietern
Also eligible: @denik, @janniklasrose, @shreyas-goenka, @lennartkats-db, @anton-107

/cmd/bundle/ - needs approval

Files: cmd/bundle/validate.go
Suggested: @pietern
Also eligible: @denik, @janniklasrose, @shreyas-goenka, @lennartkats-db, @anton-107

General files (require maintainer)

Files: libs/dyn/convert/struct_info.go, libs/structs/structtag/bundletag.go, libs/structs/structtag/bundletag_test.go
Based on git history:

• @pietern -- recent work in bundle/config/, libs/dyn/convert/

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

[eng-dev-ecosystem-bot]

Integration test report

Commit: 687b636

Run: 29102740653

	Env	💚​RECOVERED	🙈​SKIP	✅​pass	🙈​skip	Time
💚​	aws linux	4	4	230	1078	5:11
💚​	aws windows	4	4	232	1076	7:25
💚​	aws-ucws linux	4	4	316	995	6:01
💚​	aws-ucws windows	4	4	318	993	7:13
💚​	azure linux	4	4	230	1077	5:14
💚​	azure windows	4	4	232	1075	7:02
💚​	azure-ucws linux	4	4	318	992	6:07
💚​	azure-ucws windows	4	4	320	990	7:36
💚​	gcp linux	4	4	229	1079	5:28
💚​	gcp windows	4	4	231	1077	7:02

8 interesting tests: 4 RECOVERED, 4 SKIP

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

Top 10 slowest tests (at least 2 minutes):

duration	env	testname
6:28	azure-ucws windows	TestAccept
6:24	aws windows	TestAccept
6:15	aws-ucws windows	TestAccept
6:07	gcp windows	TestAccept
6:00	azure windows	TestAccept
3:03	gcp linux	TestAccept
2:55	azure linux	TestAccept
2:55	aws linux	TestAccept
2:51	aws-ucws linux	TestAccept
2:49	azure-ucws linux	TestAccept