[VC-43403] CyberArk(dataupload): replace PostDataReadingsWithOptions with PutSnapshot

[wallrj-cyberark]

Stacked on #701

Trying to untangle the CyberArk dataupload API wrapper from the DataReadings API of the agent.
The conversion between DataReadings and Snapshot will be implemented in a followup PR.

• Introduced a new Snapshot struct to represent the payload for the CyberArk Discovery and Context API.
• Replaced the PostDataReadingsWithOptions method with PutSnapshot, which now uses the Snapshot struct and removes the dependency on api.DataReadingsPost.
• Updated the retrievePresignedUploadURL method to accept clusterID directly instead of relying on Options.
• Refactored tests to align with the new PutSnapshot method and Snapshot struct. Removed unused imports and legacy test cases.

Follow up PRs

• [VC-43403] CyberArk(agent): add support for MachineHub output mode #696
• [VC-43753] CyberArk(client): add CyberArk snapshot conversion #684

Testing

I ran the data upload test with against the real API.

$ go test ./pkg/internal/cyberark/dataupload/...   -v -run RealAPI -args -testing.v 6
=== RUN   TestCyberArkClient_PutSnapshot_RealAPI
    round_trippers.go:632: I0828 13:48:33.839542] Response verb="GET" url="https://platform-discovery.integration-cyberark.cloud/api/v2/services/subdomain/tlskp-test" status="200 OK" milliseconds=325
    round_trippers.go:632: I0828 13:48:34.250080] Response verb="POST" url="https://anb5751.id.integration-cyberark.cloud/Security/StartAuthentication" status="200 OK" milliseconds=408
    identity.go:303: I0828 13:48:34.250728] made successful request to StartAuthentication source="Identity.doStartAuthentication" summary="NewPackage"
    round_trippers.go:632: I0828 13:48:34.691409] Response verb="POST" url="https://anb5751.id.integration-cyberark.cloud/Security/AdvanceAuthentication" status="200 OK" milliseconds=440
    identity.go:419: I0828 13:48:34.692008] successfully completed AdvanceAuthentication request to CyberArk Identity; login complete username="<REDACTED>"
    round_trippers.go:632: I0828 13:48:35.582159] Response verb="POST" url="https://tlskp-test.inventory.integration-cyberark.cloud/api/ingestions/kubernetes/snapshot-links" status="200 OK" milliseconds=889
    round_trippers.go:632: I0828 13:48:36.016095] Response verb="PUT" url="<REDACTED>" status="200 OK" milliseconds=433
--- PASS: TestCyberArkClient_PutSnapshot_RealAPI (2.50s)
PASS
ok      github.com/jetstack/preflight/pkg/internal/cyberark/dataupload  2.617s
```

[maelvls]

Thanks for doing that. The Options struct was odd, it looks much better now.

[maelvls]

Nothing feels off, I haven't run the tests nor tested this but the output you provided proves that the mocked tests are doing what they say they test.