Use path pattern

[uudashr]

• Use path as pattern if found, fallback to url.
• Test added

[uudashr]

Also... it would be great if we can run the test on Github Action

[lucacome]

@uudashr are you still interested in updating this PR? I've added an Action to run tests.

[uudashr]

@lucacome conflict resolved

[Copilot]

PR Overview

This PR refactors the middleware to use the request path as the operation name pattern if available, with a fallback to the URL, and adds tests to validate the behavior of the middleware options.

• Updates middleware implementation to support OperationNameFunc, SpanFilter, SpanObserver, URLTagFunc, and ComponentName options.
• Updates examples and README to use the new middleware signature with GlobalTracer and ComponentName.
• Introduces additional tests in middleware_test.go to validate operation naming, URL tagging, span filtering, error handling, and performance.

Reviewed Changes

File	Description
middleware_test.go	Adds tests covering operation naming, span observation, filtering, URL tagging, error handling, and panic recovery.
examples/server.go	Updates middleware initialization to use opentracing.GlobalTracer and ComponentName option.
README.md	Updates usage instructions to match the updated middleware signature.
middleware.go	Refactors middleware implementation to leverage new options and fallback logic for operation name and URL tags.
examples/tracer/init.go	Improves error logging in tracer initialization by switching from fmt.Println to fmt.Printf.

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