OD-2127: Restore pest detection camera trigger

[shashank-kenpath]

Summary

Restore the pest-detection camera trigger in the OAN-UI chat input and fix loader rendering while transcription or analysis is active.

Scope

• Re-enable the existing pest-detection dialog entry point.
• Make the AI and transcription Lottie loaders autoplay and stay within their containers.
• This PR changes only two UI files and targets bh-main.

Validation

• git diff --check passes.
• npm run build was attempted but the local checkout is missing vite-plugin-node-polyfills, so TypeScript stopped before Vite bundling.

Governance

• Targets bh-main through a pull request.
• Focused change with no unrelated files.