fix: components to be included in the signatureHeaders

[bcotrim-cloudflare]

Fix: custom components crash in getSigningOptions()

Problem

Passing custom components to signatureHeaders() crashes with:

TypeError: Cannot read properties of undefined (reading 'indexOf')

This happens because getSigningOptions() has two bugs on the same line:

if (signatureAgent && components.indexOf("SIGNATURE_AGENT_HEADER") === -1) {

1. components is an uninitialized local variable — should be params.components
2. "SIGNATURE_AGENT_HEADER" is a string literal — should be the variable SIGNATURE_AGENT_HEADER ("signature-agent")
   The bug was never caught because the default code path (no custom components) skips this branch entirely.

Fix

- if (signatureAgent && components.indexOf("SIGNATURE_AGENT_HEADER") === -1) {
+ if (signatureAgent && params.components.indexOf(SIGNATURE_AGENT_HEADER) === -1) {

Tests

Added tests covering custom components:

• Signing with extra headers (e.g. crawler-max-price) includes them in Signature-Input
• Rejects missing signature-agent when the header is present on the request
• Allows its absence when the header is not set

[thibmeu]

looks good overall. one suggestion to make it work for components with parameters, and another suggestion to use a generic name for headers in test instead of being tied to a product

[bcotrim-cloudflare]

looks good overall. one suggestion to make it work for components with parameters, and another suggestion to use a generic name for headers in test instead of being tied to a product

Thanks for the review, I squash committed all you improvements :)