http_server: Wildcard resource matching reports incorrect path length

[tpambor]

Describe the bug
When the HTTP server handles requests for resources defined with wildcard characters, the reported length of the matching path is incorrect. Instead of calculating the length of the requested URI, the server was incorrectly using the length of the wildcard resource definition itself.

To Reproduce
For a resource defined as /foo/*. If /foo/bar is requested the length returned is 6 and not 8.

Expected behavior
For a resource defined as /foo/*. If /foo/bar the length returned should be 8.

Impact
This bug fix ensures that the HTTP server correctly identifies the length of the matched path for wildcard resources. This resolves potential issues related to incorrect path length information being used in subsequent request processing.

Logs and console output

Environment (please complete the following information):

• OS: Linux
• Toolchain: Zephyr SDK
• Commit SHA or Version used: 4.1

Additional context

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[tpambor]

This issue has been resolved in main branch by PR #86648. Wildcard resource support was introduced in v3.7. To fully address this bug and a related deprecation warning (present since v3.7 as well), please backport both commits from the pull request 33cf7dc and 0f90aff to v3.7, v4.0, and v4.1 branches. I would suggest backporting the entire pull request as the second commit resolves a deprecation warning that also affects these versions.