docs: update VertexLabel API examples to match HugeGraph Server v1.5.0

[Swadeep006]

Purpose of the PR

• close [Improvement] RESTful API request/response content need update  #260

This PR updates the VertexLabel REST API documentation to align with
the actual HugeGraph Server v1.5.0 behavior.

Changes

• Updated Create VertexLabel request and response examples
• Corrected Get VertexLabel and List VertexLabels response formats
• Unified id_strategy usage to PRIMARY_KEY
• Updated TTL-related examples
• Added notes about PropertyKey prerequisites and Docker authentication behavior

All examples were verified using a local HugeGraph 1.5.0 Docker setup.

[VGalaxies]

@imbajin, have the APIs for 1.5.0 and 1.7.0 changed (ignoring graphspace for now)?

@Swadeep006, please update the Chinese documentation as well, could use LLM to assist :)

[Swadeep006]

Hi @VGalaxies ,CN documentation has been updated and kept in sync with EN. once check it!

[imbajin]

@Swadeep006 Hi, we should use 1.7.0 as the docker image version (also need update 1.5.0 → 1.7.0 in all docs)

due to graphspace feature will influence almost all APIs → https://hugegraph.apache.org/docs/clients/restful-api/

If this hint/note isn't working well, let's consider adding a universal header to all API pages. This way, we can clearly notify users at the top of the page to check the old documentation if their server version is prior to 1.7.

also cc @VGalaxies