Add TimeZone header support to REST API (#17344)

[Lexert19]

Description

This PR adds support for the X-TimeZone header in REST API V2. The header is parsed in AuthorizationFilter and the time zone is set in the session. Integration tests are added to verify correct handling of valid and invalid time zones.

Closes #17344

---

This PR has:

• been self-reviewed.
  • concurrent read
  • concurrent write
  • concurrent read and write
• added documentation for new or modified features or behaviors.
• added Javadocs for most classes and all non-trivial methods.
• added or updated version, license, or notice information
• added comments explaining the "why" and the intent of the code wherever would not be obvious
  for an unfamiliar reader.
• added unit tests or modified existing tests to cover new code paths, ensuring the threshold
  for code coverage.
• added integration tests.
• been tested in a test IoTDB cluster.

---

Key changed/added classes (or packages if there are too many classes) in this PR

[HTHou]

Add support in
https://github.com/apache/iotdb/blob/master/external-service-impl/rest/src/main/java/org/apache/iotdb/rest/protocol/table/v1/impl/RestApiServiceImpl.java and https://github.com/apache/iotdb/blob/master/external-service-impl/rest/src/main/java/org/apache/iotdb/rest/protocol/v1/impl/RestApiServiceImpl.java ?

[HTHou]

Another question, why did you pick X-TimeZone? I found there is a document uses Time-Zone.
https://docs.github.com/en/rest/using-the-rest-api/timezones-and-the-rest-api?apiVersion=2026-03-10#using-the-time-zone-header

[HTHou]

And consider add some example in https://github.com/apache/iotdb/tree/master/example/rest-java-example/src/main/java/org/apache/iotdb?

[Lexert19]

Hi @HTHou, thank you for the review! I've updated the PR:

• Renamed header to Time-Zone
• Added support to V1 and Table V1 API
• Added examples
• Added integration tests for V1 and V2, following the existing code style