feat(FR-1448): allow user to select multi agents when creating multi-node session

[nowgnuesLee]

resolves #4256 (FR-1448)

This PR adds support for selecting multiple agents when launching a session, available for Backend.AI manager version 25.15.0 and above.

Key changes:

• Modified AgentSelect component to handle multiple agent selection
• Updated agent selection logic in ResourceAllocationFormItems to support multi-agent mode
• Added special handling for the "auto" option in multi-select mode
• Implemented proper agent_list generation in session creation payload
• Added 'multi-agents' feature detection for manager version 25.15.0+
• Changed agent default value from string to array format ['auto']
• Removed restrictions that previously disabled cluster settings when a specific agent was selected

for testing, using test server which supports multi node session

how to test:

• single mode
  • Please verify that the agent_list is sent as a string[] when using multi-agents.
• multi mode
  • In versions 25.14 and below, the length of the agent_list must be equal to the cluster_size.
  • Please verify that the agent_list is being passed as a string array when using multi-agents.

Checklist:

• Documentation
• Minium required manager version: 25.15.0
• Specific setting for review
• Minimum requirements to check during review
• Test case(s) to demonstrate the difference of before/after

[nowgnuesLee]

• feat(FR-1448): allow user to select multi agents when creating multi-node session #4309 👈 (View in Graphite)
• main

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[Copilot]

Pull Request Overview

This PR enables multi-agent selection when creating multi-node sessions for Backend.AI manager version 25.15.0 and above. It transforms the agent selection from a single dropdown to a multi-select component while maintaining backward compatibility.

• Added 'multi-agents' feature detection for manager version 25.15.0+
• Modified AgentSelect component to support multiple agent selection with special "auto" handling
• Updated session creation payload logic to properly handle agent arrays and cluster size requirements

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
src/lib/backend.ai-client-esm.ts	Added feature flag detection for multi-agents support
react/src/pages/SessionLauncherPage.tsx	Updated session creation payload logic and default agent value format
react/src/components/ResourceAllocationFormItems.tsx	Modified form to support multi-agent selection and removed cluster restrictions
react/src/components/AgentSelect.tsx	Enhanced component to handle multiple selection with auto option logic

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[github-actions]

Coverage report for ./react

St.❔	Category	Percentage	Covered / Total
🔴	Statements	4.41% (-0.01% 🔻)	501/11352
🔴	Branches	3.55% (-0.01% 🔻)	285/8019
🔴	Functions	2.55% (-0% 🔻)	90/3529
🔴	Lines	4.39% (-0.01% 🔻)	487/11096

Show files with reduced coverage 🔻

St.❔	File	Statements	Branches	Functions	Lines
🔴	... / AgentSelect.tsx	3.7% (-1.3% 🔻)	0%	0%	3.7% (-1.3% 🔻)
🔴	... / ResourceAllocationFormItems.tsx	13.92% (+0.06% 🔼)	9.74% (-0.06% 🔻)	12.16%	13.68% (+0.06% 🔼)

Test suite run success

114 tests passing in 13 suites.

Report generated by 🧪jest coverage report action from f0ef289

[ironAiken2]

please resolve the conflicts :)

[yomybaby]

Code improvements

1. ResourceAllocationFormItems.tsx

• Improved code readability by removing spread operator and passing props directly
• mode and labelRender props are now more explicitly defined

2. SessionLauncherPage.tsx

• Simplified array handling by replacing Array.isArray() check with _.castArray()
• Better utilization of lodash utility function for cleaner code

[agatha197]

please resolve the conflicts. and is there any test node? you can reply it in jira comment or teams.