feat(planet): implement progressive rendering for project gallery

[e-esakman]

Summary

Improves project loading in GlobalPlanet by introducing progressive rendering. Projects are now displayed incrementally as their data arrives instead of waiting for all requests to complete.

Problem

The previous implementation of downloadProjectsToCache followed an "all-or-nothing" approach:

• Used individual XHR requests for each project (N+1 pattern)
• Waited for all requests to complete before rendering
• Rendered everything in a single batch

Impact:

• Users experienced long loading times (10+ seconds on slow connections)
• UI remained blank with only a loading spinner
• Poor perceived performance due to the N+1 request pattern

PR Category

• Bug Fix - Fixes a bug or incorrect behavior
• Feature - Adds new functionality
• Performance - Improves performance
• Tests - Adds or updates test coverage
• Documentation - Updates docs

Key Changes

• Separated fetching and rendering: Introduced renderSingleProjectSafe to inject cards into the DOM immediately upon successful request completion.
• Guards for Duplicate Rendering: Added checks against this.cards to prevent duplicate project cards during asynchronous race conditions
• DOM Efficiency: Refactored jQuery.tooltip initialization to fire once per batch instead of per project, reducing redundant DOM traversal and reduncing unnecessary CPU call.
• Improved Error Handling: The "Feature unavailable" message is now triggered only if the entire batch fails. If at least one project loads, the UI still displays available content

Checklist

• I have tested these changes locally and they work as expected.
• I have added/updated tests that prove the effectiveness of these changes.
• I have updated the documentation to reflect these changes, if applicable.
• I have followed the project's coding style guidelines.
• I have run npm run lint and npx prettier --check . with no errors.
• I have addressed the code review feedback from the previous submission, if applicable.

Notes

• this PR does not eliminate the N+1 request pattern at the network level, as the current API only provides per-project detail endpoints.
• it improves UX by mitigating its impact through progressive rendering.

[github-actions]

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

[zealot-zew]

There is a duplicate PR #6101 on the same feature you are trying to work. i suppose the other PR is tend to go stale, so your PR is a good addition. you can refer to that PR if that helps making better contribution, in the mean time ill give this a test.

[zealot-zew]

It working good. Planet seems to be slow, but its fine for now.

Screen.Recording.2026-04-13.093059.mp4