fix: select previous item correctly when deleting from 2-item collection

[Manasvibansal1]

PR Description

When exactly 2 requests exist and the non-first one is deleted,
itemIds.length > 1 evaluates to false (1 item remains), so newId
falls through to null leaving the main panel blank even though one
request still exists.

Fix: Replace itemIds.length > 1 with idx > 0, mirroring the
existing removeEnvironment logic.

Related Issues

• Closes bug: Deleting second-of-two requests leaves selection null #1710

Checklist

• I have gone through the contributing guide
• I have updated my branch and synced it with project main branch before making this PR
• I am using the latest Flutter stable branch (run flutter upgrade and verify)
• I have run the tests (flutter test) and all tests are passing

Added/updated tests?

We encourage you to add relevant test cases.

• Yes
• No, This is a one-line logic fix with no new functionality. Existing tests cover this path.

OS on which you have developed and tested the feature?

• Windows
• macOS
• Linux

[Manasvibansal1]

Hi, I've opened a PR with the fix , replacing itemIds.length > 1 with idx > 0 to mirror the removeEnvironment logic. PR: #1714