Summary

Fixes a bug where https://host/api/v1/ (trailing slash after /api/v1) was incorrectly expanded to https://host/api/v1/api/v1 because strings.TrimSuffix only removed a single trailing slash before the suffix check.

Closes #62

Changes

• Extract NormalizeServerURL(raw string) string that trims all trailing slashes with strings.TrimRight before the /api/v1 suffix check
• Replace the inline normalization in NewAPIClientWithKeyAndTransport with a call to NormalizeServerURL
• Add table-driven tests covering bare host, single/multiple trailing slashes, already-correct URL, trailing slash on /api/v1, empty string, and slash-only input

Test plan

• go test -v ./... passes
• go fmt ./... produces no diff
• go build succeeds

Checklist

• New tests added for new behaviour
• Documentation updated (README, command --help, comments)
• No unrelated changes included