Document what OpenTelemetry defaults make sense to change for use with Sentry

### Description

Document what OpenTelemetry defaults make sense to change for use with Sentry, e.g.:
- ~~MongoDB queries do not have values but just `?` placeholders in the statement, there is a flag to change this in OpenTelemetry (https://opentelemetry.io/docs/zero-code/java/agent/instrumentation/#db-statement-sanitization)~~ we don't want to be recording query values
- HTTP headers are missing

Also add a note to warn about potential PII.

首先定位儲存庫的 OpenTelemetry 文件，並檢閱連結的 OpenTelemetry Java agent instrumentation 指南。記錄哪些預設值適用於 Sentry，保留不記錄查詢值的決定，涵蓋 HTTP headers，並新增關於可能包含 PII 的警告。

由索引模型根據 Issue 內容生成。