Fix #59: Parse comma-separated IP chains in non-RFC forwarded headers

[samdark]

• parse comma-separated IP chains from non-RFC forwarded headers
• preserve PSR-7 header value order and trim optional whitespace
• reject malformed empty chain entries through existing IP validation
• document the behavior and add regression coverage for X-Forwarded-For and custom headers

Fixes #59

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.67%. Comparing base (e6f3d84) to head (224ec97).

Additional details and impacted files

@@            Coverage Diff            @@
##             master      #60   +/-   ##
=========================================
  Coverage     98.67%   98.67%           
+ Complexity      142      141    -1     
=========================================
  Files             3        3           
  Lines           376      378    +2     
=========================================
+ Hits            371      373    +2     
  Misses            5        5           

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[Copilot]

Pull request overview

This PR fixes issue #59 by teaching TrustedHostsNetworkResolver to correctly parse common proxy behavior where X-Forwarded-For (and similar non-RFC “separate header group” IP headers) arrive as a single comma-separated header line in PSR-7 requests, splitting and trimming the IP chain before validation/chain resolution.

Changes:

• Update non-RFC forwarded header parsing to split comma-separated IP chains (using PSR-7 getHeaderLine()), trimming optional whitespace and letting existing IP validation reject empty segments.
• Add/adjust PHPUnit coverage for comma-separated X-Forwarded-For and custom header groups, including multiple header values.
• Document the new behavior in README and note the fix in the changelog.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/TrustedHostsNetworkResolver.php	Parse non-RFC forwarded IP header lines as comma-separated lists (trimmed) before building the connection chain.
tests/TrustedHostsNetworkResolver/ProcessTest.php	Add regression tests for comma-separated IP chains in X-Forwarded-For and custom headers (including multiple header values).
tests/TrustedHostsNetworkResolver/RuntimeExceptionTest.php	Add coverage ensuring empty comma-separated segments are rejected via existing IP validation.
README.md	Document comma-separated parsing behavior and combination of multiple header values in original order.
CHANGELOG.md	Record the bugfix for #59 under the next development version.

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