Bug Description

The hasDirective function in the cache middleware only recognizes a directive when it's followed by a comma (,) or end-of-string. It does not account for directives followed by a space, tab, or = (for directives with arguments).

This means headers like:

• Pragma: no-cache (trailing space) — no-cache is not detected
• Cache-Control: private (trailing space) — private is not detected
• Cache-Control: no-cache="Set-Cookie" — no-cache is not detected

This can cause the cache middleware to serve cached responses when it shouldn't (e.g., a private response could leak into the shared cache, or a no-cache Pragma hint could be ignored).

How to Reproduce

// These all incorrectly return false:
hasDirective("no-cache ", "no-cache")             // trailing space → false (should be true)
hasDirective("no-cache\t", "no-cache")            // trailing tab → false (should be true)
hasDirective(`no-cache="Set-Cookie"`, "no-cache") // directive with value → false (should be true)
hasDirective("private ", "private")               // trailing space → false (should be true)

Expected Behavior

hasDirective should recognize a directive as matched when it is followed by end-of-string, ,, , \t, or =, since all of these are valid terminators for a Cache-Control directive token per RFC 9111.

Fiber Version

v3 (main)

Checklist:

• I agree to follow Fiber's Code of Conduct.
• I have checked for existing issues that describe my problem prior to opening this one.
• I understand that improperly formatted bug reports may be closed without explanation.