test: add unit tests for compileQueryParser, compileTrust, and normalizeTypes

[tommyhgunz14]

Summary

Adds comprehensive test coverage for three previously untested utility functions in lib/utils.js.

Problem

The following utility functions in lib/utils.js had no dedicated unit tests:

• compileQueryParser() — compiles the query parser setting into a function
• compileTrust() — compiles the proxy trust setting into a function
• normalizeTypes() — normalizes an array of type strings to MIME type objects

While compileETag() recently received test coverage (PR #6534), these three sibling functions remained untested.

Changes

Added 17 new test cases to test/utils.js:

compileQueryParser() (8 tests)

• Returns a function for true and 'simple'
• Parses simple query strings correctly
• Returns a function for 'extended' and parses nested query strings
• Returns undefined for false
• Passes through custom functions
• Throws TypeError for unknown string values

compileTrust() (5 tests)

• Returns a function that always returns true for true
• Passes through custom functions
• Supports numeric hop count (returns true for indices below the threshold)
• Supports comma-separated string values
• Returns a function for undefined/falsy values

normalizeTypes() (4 tests)

• Normalizes shorthand types ('html' → 'text/html')
• Handles full MIME types
• Handles empty arrays
• Handles MIME types with quality parameters

Testing

All 37 tests pass (21ms):

37 passing (21ms)

Test style follows the existing patterns used in compileETag and normalizeType test suites.