Stabilize pagination state and dataset reconciliation

[ash1shkumar]

Description

This PR improves pagination reliability when datasets change during navigation. It introduces pagination reconciliation mechanisms, mutation detection, and boundary normalization to ensure consistent pagination state even when activity items are added, removed, or updated while users are browsing.

Fixes #366

Changes Made

• Added pagination snapshot tracking for dataset state validation.
• Introduced dataset mutation detection between pagination states.
• Added pagination reconciliation logic to normalize visible item boundaries.
• Implemented pagination diagnostics for mutation and reconciliation monitoring.
• Memoized grouped activity calculations to reduce unnecessary recomputation.
• Added hidden diagnostic metadata for pagination state verification and debugging.
• Improved handling of dataset updates during navigation scenarios.

Testing

• Verified pagination remains consistent when dataset size changes.
• Tested boundary normalization with varying item counts.
• Confirmed grouped activity rendering remains accurate after mutations.
• Validated reconciliation and mutation tracking metrics update correctly.
• Ensured activity feed navigation behaves predictably during dataset updates.

Expected Labels

level3, NSoC'26

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Project	Deployment	Actions	Updated (UTC)
flow-forge	Ready	Preview, Comment	Jun 15, 2026 4:36pm