Refactor and optimize feed ranking and pagination logic

[ash1shkumar]

📌 Description

This PR improves the activity feed system by refining ranking logic, stabilizing pagination, and optimizing aggregation performance across tasks and messages.

The goal is to ensure consistent ordering, better scalability, and predictable feed behavior under load.

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🚀 Changes Introduced

• Refactored feed ranking algorithm for better determinism
• Improved engagement + recency scoring balance
• Stabilized pagination slicing logic
• Reduced redundant recalculations in feed transformation pipeline
• Optimized mapping of tasks and messages into unified feed items
• Improved sorting consistency with stable fallback ordering

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⚙️ Technical Improvements

• Deterministic ranking using combined scoring system
• Stable ordering using insertion index as final fallback
• Reduced unnecessary object re-computation during sorting
• Improved feed aggregation pipeline clarity
• Safer handling of missing or malformed timestamps

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🧠 Why This Matters

Without this improvement:

• Feed ordering may vary under similar datasets
• Pagination can become inconsistent
• Ranking may fluctuate under rapid updates

With this fix:

• Predictable feed ordering
• Stable pagination results
• Better user experience during activity bursts

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🧪 Testing Done

• Verified ranking stability across multiple datasets
• Tested pagination consistency across pages
• Simulated concurrent feed updates
• Validated ordering determinism

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Fixes #359

📦 Acceptance Criteria

• Stable ranking output
• Correct pagination behavior
• No regression in feed structure
• Improved performance under load

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🏷️ Expected Labels

level3, NSoC'26

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Project	Deployment	Actions	Updated (UTC)
flow-forge	Ready	Preview, Comment	Jun 15, 2026 6:12pm