[BUG]: Portfolio floods RPC with ~23k requests during idle

[rohans02]

Bug Description

• With a wallet connected and positions held, the portfolio page fires ~23,673 RPC requests over a 60-second idle window (no user interaction). This exhausts the public RPC's rate limit (429s + CORS blocks), which breaks the getLogs cost-basis scan, so P&L renders as -100%.

• Root cause: useIndexedDB and its wrapper useFatePoolsStorage each return a fresh object literal every render. The portfolio effect that depends on storage sees a new identity each render, re-runs, sets state with a new array, and re-renders, looping indefinitely.

Steps to Reproduce

1. Connect a wallet on Sepolia with at least one held position.
2. Open /portfolio and leave it idle (no interaction).
3. Open DevTools > Network, filter RPC: request count climbs into the thousands within 60 seconds.
4. P&L shows -100% because the getLogs scan is rate-limited out.

Logs and Screenshots

Environment Details

• OS: Windows 11
• Browser: Chrome / Brave
• Next.js 15 static export, wagmi + viem
• Chain: Sepolia (11155111), wallet connected, 3 held positions

Impact

High - Major feature is broken

Code of Conduct

• I have joined the Discord server and will post updates there
• I have searched existing issues to avoid duplicates