feat(planet): Add client-side rate limiting and caching for Planet API

[shoryabansalgithub]

This PR introduces client-side rate limiting and caching for Planet API calls to improve reliability, reduce server load, and enable offline access to previously viewed projects.

Closes #5096

Changes

New Files

• planet/js/RequestManager.js - Handles rate limiting, request throttling, and retry logic
• planet/js/CacheManager.js - IndexedDB-based caching for project metadata and data
• planet/js/__tests__/RequestManager.test.js - Unit tests (15 tests)
• planet/js/__tests__/CacheManager.test.js - Unit tests (17 tests)

Modified Files

• planet/js/ServerInterface.js - Integrated rate limiting and caching
• planet/index.html - Added script tags for new modules

Features

Rate Limiting & Throttling

• Minimum 500ms delay between consecutive API calls
• Maximum 3 concurrent requests with queue management
• Request deduplication (duplicate concurrent requests share same promise)

Retry Logic with Exponential Backoff

• Up to 3 retry attempts on connection failures
• Exponential backoff (1s → 2s → 4s delays)
• Graceful degradation with failure responses

IndexedDB Caching

• Project metadata cached for 24 hours
• Full project data cached for 7 days
• LRU eviction when cache exceeds 100 projects
• Automatic expired entry cleanup

Statistics & Monitoring

• Track total requests, cached responses, retries, and failures
• getStats() method for debugging

Testing

• 32 new unit tests added
• All 2162 existing tests continue to pass

Backward Compatibility

The existing API remains fully backward compatible. No changes required for existing code.

[github-actions]

✅ All Jest tests passed! This PR is ready to merge.

[vyagh]

heyy, I think you forgot to link this to your Issue

[shoryabansalgithub]

heyy, I think you forgot to link this to your Issue