refactor: replace manual contains helper with slices.Contains

[Copilot]

pkg/hub/server/routes.go had hand-rolled contains and containsAll slice helpers that duplicate functionality available in the stdlib slices package since Go 1.21. This project targets Go 1.25.

Changes

• Removed contains(set []string, e string) bool — replaced inline with slices.Contains
• Updated containsAll to call slices.Contains directly
• Added "slices" to imports

// Before
func contains(set []string, e string) bool {
    for _, s := range set {
        if s == e {
            return true
        }
    }
    return false
}

func containsAll(set []string, subset []string) bool {
    for _, se := range subset {
        if !contains(set, se) {
            return false
        }
    }
    return true
}

// After
func containsAll(set []string, subset []string) bool {
    for _, se := range subset {
        if !slices.Contains(set, se) {
            return false
        }
    }
    return true
}

No behavior change.

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.