feat: improve astronomy-loadgen memory management and AI response han…

[hagen-p]

…dling

This update significantly improves the load generator's memory efficiency and AI interaction handling:

Memory Optimizations:

• Implement browser reuse pattern to prevent memory leaks from repeated browser launches
• Add --aggressive-cache-discard Chrome flag to prevent cache accumulation
• Only close pages between cycles, not the entire browser process
• Add ensureBrowser() function for connection health checking

AI Response Improvements:

• Wait for AI responses using correct [data-cy='AIAnswer'] selector
• Add proper delays (500ms pre-request, 1500ms post-response) for complete telemetry capture
• Implement graceful 15s timeout with fallback for slow AI responses
• Ensure RUM telemetry captures full AI interaction lifecycle

Feature Enhancements:

• Support multiple random product ordering (1-3 products per cycle)
• Add configurable product IDs via PRODUCT_IDS env variable
• Add configurable cycle delay via CYCLE_DELAY_MS env variable (default: 1000ms)
• Improved logging with detailed progress indicators

This makes the load generator suitable for long-running scenarios without memory accumulation issues.

Changes

Please provide a brief description of the changes here.

Merge Requirements

For new features contributions, please make sure you have completed the following
essential items:

• CHANGELOG.md updated to document new feature additions
• Appropriate documentation updates in the docs
• Appropriate Helm chart updates in the helm-charts

Maintainers will not merge until the above have been completed. If you're unsure
which docs need to be changed ping the
@open-telemetry/demo-approvers.