Perf: Implement LRU node eviction in AsyncDataTree to prevent OOM

[Ayush Gupta (Ayush-kathil)]

Fixes

Fixes #332420

Description

What this PR does:
This PR addresses OOM (Out Of Memory) crashes in the Renderer when dealing with massive workspaces by capping the memory footprint of the AsyncDataTree.

When opening massive workspaces (e.g., mono-repos with 500k+ files) or returning massive search results, expanding the Explorer tree causes the AsyncDataTree to materialize hundreds of thousands of nodes in memory. Even though the DOM is virtualized via listWidget.ts, the in-memory metadata for these nodes scales linearly until the browser engine exhausts its memory limit.

Architectural Changes:

• Introduces a strict LRU (Least Recently Used) cache mechanism directly into src/vs/base/browser/ui/tree/asyncDataTree.ts.
• Hooks into _onDidChangeCollapseState to track node access history.
• Runs an asynchronous background Garbage Collector interval (performGarbageCollection).
• When the internal node count exceeds MAX_RETAINED_NODES (default 50k), the tree automatically collapses and evicts the least recently rendered nodes outside of the current viewport.

Verification Steps

1. Open a workspace with >500,000 files.
2. Recursively expand the root node in the Explorer to aggressively materialize tree nodes.
3. Monitor the Renderer memory footprint in the Task Manager or Activity Monitor.
4. Verify that the memory footprint plateaus instead of growing unboundedly until an OOM crash.

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[vs-code-engineering]

📬 CODENOTIFY

The following users are being notified based on files changed in this PR:

Benjamin Christopher Simmonds (@benibenj)

Matched files:

• src/vs/base/browser/ui/tree/asyncDataTree.ts

[Ayush Gupta (Ayush-kathil)]

@microsoft-github-policy-service agree

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[Ayush Gupta (Ayush-kathil)]

Hi Benjamin Christopher Simmonds (@benibenj) , Kindly Look into this PR if you need further any changes please let me know