feat(ai-proxy): support Google Cloud Vertex

[HecarimV]

Ⅰ. Describe what this PR did

support Google Cloud Vertex provider

Ⅱ. Does this pull request fix one issue?

fix: #1697

Ⅳ. Describe how to verify it

docker-compose.yaml

version: '3.7'
services:
  envoy:
    image: higress-registry.cn-hangzhou.cr.aliyuncs.com/higress/gateway:v1.4.0-rc.1
    entrypoint: /usr/local/bin/envoy
    # 开启了 debug 级别日志方便调试
    command: -c /etc/envoy/envoy.yaml --component-log-level wasm:debug
    networks:
      - higress-net
    ports:
      - "10000:10000"
    volumes:
      - ./envoy.yaml:/etc/envoy/envoy.yaml
      - ./plugin.wasm:/etc/envoy/plugin.wasm
networks:
  higress-net: {}

envoy.yaml

# File generated by hgctl. Modify as required.

admin:
  address:
    socket_address:
      protocol: TCP
      address: 0.0.0.0
      port_value: 9901
static_resources:
  listeners:
    - name: listener_0
      address:
        socket_address:
          protocol: TCP
          address: 0.0.0.0
          port_value: 10000
      filter_chains:
        - filters:
            - name: envoy.filters.network.http_connection_manager
              typed_config:
                "@type": type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManager
                scheme_header_transformation:
                  scheme_to_overwrite: https
                stat_prefix: ingress_http
                # Output envoy logs to stdout
                access_log:
                  - name: envoy.access_loggers.stdout
                    typed_config:
                      "@type": type.googleapis.com/envoy.extensions.access_loggers.stream.v3.StdoutAccessLog
                # Modify as required
                route_config:
                  name: local_route
                  virtual_hosts:
                    - name: local_service
                      domains: [ "*" ]
                      routes:
                        - match:
                            prefix: "/"
                          route:
                            cluster: vertex
                            timeout: 300s
                http_filters:
                  - name: wasmtest
                    typed_config:
                      "@type": type.googleapis.com/udpa.type.v1.TypedStruct
                      type_url: type.googleapis.com/envoy.extensions.filters.http.wasm.v3.Wasm
                      value:
                        config:
                          name: wasmtest
                          vm_config:
                            runtime: envoy.wasm.runtime.v8
                            code:
                              local:
                                filename: /etc/envoy/plugin.wasm
                          configuration:
                            "@type": "type.googleapis.com/google.protobuf.StringValue"
                            value: |
                              {
                                "provider": {
                                  "type": "vertex",                                
                                  "apiTokens": [
                                    "your-api-token"
                                  ],
                                  "geminiSafetySetting": {
                                    "HARM_CATEGORY_DANGEROUS_CONTENT": "OFF",
                                    "HARM_CATEGORY_HARASSMENT": "OFF",
                                    "HARM_CATEGORY_HATE_SPEECH": "OFF",
                                    "HARM_CATEGORY_SEXUALLY_EXPLICIT": "OFF"
                                  },       
                                  "vertexProjectId": "eastern-concord-457601-e9",
                                  "vertexRegion": "us-central1"
                                }
                              }
                  - name: envoy.filters.http.router
  clusters:
    - name: vertex
      connect_timeout: 30s
      type: LOGICAL_DNS
      dns_lookup_family: V4_ONLY
      lb_policy: ROUND_ROBIN
      load_assignment:
        cluster_name: vertex
        endpoints:
          - lb_endpoints:
              - endpoint:
                  address:
                    socket_address:
                      address: us-central1-aiplatform.googleapis.com
                      port_value: 443
      transport_socket:
        name: envoy.transport_sockets.tls
        typed_config:
          "@type": type.googleapis.com/envoy.extensions.transport_sockets.tls.v3.UpstreamTlsContext
          "sni": "us-central1-aiplatform.googleapis.com"

测试非流式请求：

curl -X POST 'http: //localhost:10000/v1/chat/completions' \
  -H 'Content-Type: application/json' \
  -d '{
    "model": "gemini-2.0-flash-001",
    "messages": [
        {
            "role": "user",
            "content": "你好，你是谁？"
        }
    ],
    "max_tokens": 100,
    "temperature": 0.3,
    "stream": false
}'

测试流式请求：

curl -X POST 'http: //localhost:10000/v1/chat/completions' \
  -H 'Content-Type: application/json' \
  -d '{
    "model": "gemini-2.0-flash-001",
    "messages": [
        {
            "role": "user",
            "content": "你好，你是谁？"
        }
    ],
    "stream": true
}'

Ⅴ. Special notes for reviews

vertex api 文档：https://cloud.google.com/vertex-ai/generative-ai/docs/model-reference/inference

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 46.06%. Comparing base (ef31e09) to head (a0336cb).
Report is 524 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #2119       +/-   ##
===========================================
+ Coverage   35.91%   46.06%   +10.15%     
===========================================
  Files          69       81       +12     
  Lines       11576    13010     +1434     
===========================================
+ Hits         4157     5993     +1836     
+ Misses       7104     6671      -433     
- Partials      315      346       +31     

see 78 files with indirect coverage changes

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[CH3CHO]

我改了一点格式问题，麻烦pull一下。

[CH3CHO]

现在是每次请求都去调用认证服务吗？这个开销会不会有点太大了。