perf(scan): skip eth_getLogs factory walk in global LabelProvider

[satyakwok]

Summary

Problem: Browser-walked scan v1 home page → 200+ RPC POSTs to rpc.sentrixchain.com within ~30s of cold page load. Source: LabelProvider (root layout, fires on every page mount) calls fetchTokens(network), which fans out to a 117-chunk eth_getLogs walk against TokenFactory v1.1.0 covering ~590K blocks since deploy.

Fix: Split out fetchTokensForLabels = fetchNativeTokens — REST-only, no factory walk. Used by LabelProvider. Pages that actually consume the EVM token list (/tokens, TokenRanking) keep calling the full fetchTokens which still walks.

Why it's safe

• Native token entries from /tokens REST endpoint (currently empty on mainnet) still feed LabelProvider.
• Validator names, treasury labels, governance addresses, premine wallets all come from STATIC_LABELS + fetchValidators + fetchAccountsTop — unaffected.
• EVM token symbols only show as labels on tx-list / address-list rows. Currently scan v1 has 2 factory-deployed tokens (SGC + TECU). Their badges won't appear in tx lists until either (a) a user visits the token detail page (which triggers its own fetch) or (b) the chain /tokens REST endpoint starts returning EVM-factory entries (chain-side indexer follow-up).

Verification

curl https://api.sentrixchain.com/tokens
# { "tokens": [], "total": 0 } — REST endpoint returns empty, so this PR doesn't lose anything that was rendering

Before: home page network panel shows ~200 POSTs to rpc.sentrixchain.com in the first minute (mostly eth_getLogs from the walk).
After: ~10 POSTs (viem block-watch only).

Test plan

• Open scan.sentrixchain.com/en → confirm no eth_getLogs burst in network panel
• Open scan.sentrixchain.com/en/tokens → confirm SGC + TECU still render (own useTokens walk)
• pnpm --filter=@sentriscloud/scan typecheck green (verified locally)

Summary by CodeRabbit

• Performance Improvements
  • Optimized token label loading by switching to a more efficient data retrieval method, reducing latency and improving responsiveness when accessing token label information throughout the application.

[coderabbitai]

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ℹ️ Recent review info

⚙️ Run configuration

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Plan: Pro Plus

Run ID: 6bd73adb-d6d5-48fb-9021-0e76d0476126

📥 Commits

Reviewing files that changed from the base of the PR and between 348ab67 and a92ca93.

📒 Files selected for processing (2)

• apps/scan/lib/api.ts
• apps/scan/lib/labels.tsx

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📝 Walkthrough

Walkthrough

This PR optimizes token label resolution by introducing fetchTokensForLabels, a lightweight REST-only variant that replaces the heavier EVM factory log walk. A new export in api.ts aliases fetchTokensForLabels to the existing fetchNativeTokens function. The LabelProvider in labels.tsx is updated to call fetchTokensForLabels instead of fetchTokens during its network effect, reducing overhead while maintaining the same downstream logic for building label entries from token data.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~5 minutes

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title directly describes the main change: replacing the heavy eth_getLogs factory walk with a lighter approach in the LabelProvider, which is the core performance optimization.
Description check	✅ Passed	The description covers all required template sections with substantial detail: Summary explains the problem and fix clearly, Why it's safe provides important context, Verification demonstrates the improvement, and Test plan provides checkboxes for manual testing.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch perf/scan-label-provider-no-evm-walk

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