fix(frontend): restore click-to-open for side elements

[axelray-dev]

Summary

Since 2.11.0, the element side panel opened automatically whenever a message with display="side" elements arrived. In 2.10.x the panel only opened when the user clicked the element link. Closing the panel did not stick, because the next side-element update forced it open again.

Changes

• In MessagesContainer, stop auto-calling setSideView when side elements change.
• Still clear sideView when no side elements remain so a closed/stale panel does not linger.
• Leave click-to-open via onElementRefClick unchanged.
• Add Vitest coverage: new side elements do not auto-open; clearing elements clears an open side view.

Verification

• Vitest frontend/tests/MessagesContainer.spec.tsx (2 tests)
• ESLint, Prettier, and frontend typecheck on touched files

Fixes #2979

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Summary by cubic

Restores click-to-open for side elements and stops auto-opening the side panel. Fixes #2979.

• Bug Fixes
  • Removed auto setSideView in MessagesContainer when side elements update.
  • Clear sideView when no side elements remain to avoid stale panels.
  • Keep onElementRefClick for manual open; add Vitest tests to cover non-auto-open and clearing.

^{Written for commit a76630e. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 2 files

_{Re-trigger cubic}