Missing dependency information: require local opentelemetry-util-genai extended but not automatically installed

### What problem do you want to solve?

The loongsuite-instrumentation-* like loongsuite-instrumentation-agentscope package depends on an extended version of opentelemetry-util-genai that includes additional features like ExtendedTelemetryHandler and ExtendedInvocationMetricsRecorder. However, this dependency requirement is not clearly communicated or automatically resolved during installation.

Current Issues:
Users encounter ImportError or AttributeError at runtime when the code tries to use extended features that don't exist in the opentelemetry-util-genai PyPI version.

### Describe the solution you'd like

Add clear installation instructions in the README files of instrumentation packages that depend on the extended opentelemetry-util-genai.

### Describe alternatives you've considered

Use direct path references in pyproject.toml to automatically install the local extended version:
dependencies = [
"opentelemetry-util-genai @ {root:uri}/../../util/opentelemetry-util-genai",
]

[tool.hatch.metadata]
allow-direct-references = true

### Additional Context

_No response_

### Would you like to implement a fix?

Yes

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