feat: add cluster session routing for DQL

[shanghaikid]

Summary

• Add MilvusClient.session(clusterId) for lightweight DQL sessions pinned to a target cluster.
• Route cluster_id through search params, hybrid search rank params, and query params, including iterator paths.
• Update proto submodule/proto-json to latest 3.0 proto with external_spec in refresh job info.

Test plan

• yarn proto:json
• yarn tsc --noEmit
• NODE_ENV=dev npx jest test/grpc/MilvusClient.spec.ts -t "session|cluster id" --runInBand
• NODE_ENV=dev npx jest test/utils/Search.spec.ts test/utils/Data.spec.ts --runInBand
• NODE_ENV=dev npx jest test/grpc/MilvusClient.spec.ts test/utils/Search.spec.ts test/utils/Data.spec.ts --runInBand --coverage --collectCoverageFrom='milvus/MilvusClient.ts' --collectCoverageFrom='milvus/const/defaults.ts' --collectCoverageFrom='milvus/grpc/Data.ts' --collectCoverageFrom='milvus/utils/Search.ts' --coverageReporters=text --testPathIgnorePatterns=cloud.spec.ts --testPathIgnorePatterns=serverless.spec.ts --testPathIgnorePatterns=GlobalCluster.spec.ts --no-cache
• Manual UAT session smoke test against Zilliz Cloud endpoint: session.query, session.get, and session.search returned Success.

[sre-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: shanghaikid

The full list of commands accepted by this bot can be found here.

Details

Needs approval from an approver in each of these files:

• OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.50%. Comparing base (d999496) to head (9f2795d).
⚠️ Report is 5 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #558      +/-   ##
==========================================
+ Coverage   97.47%   97.50%   +0.02%     
==========================================
  Files          61       61              
  Lines        4877     4922      +45     
  Branches     1380     1389       +9     
==========================================
+ Hits         4754     4799      +45     
  Misses        123      123              

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.