feat: normalize gRPC backfill

[thlorenz]

Summary

Normalize gRPC backfill handling so every gRPC endpoint is treated as backfill-capable, and all subscription paths consistently derive from_slot from the shared chain slot.

Details

magicblock-chainlink

• Removed provider-specific gRPC endpoint gating and backfill capability detection. Generic gRPC endpoints with an API key are now accepted instead of only Helius/Triton-shaped URLs.
• Made ChainSlot::compute_from_slot() return a concrete slot value, saturating to 0 during bootstrap or low-slot cases.
• Updated account, optimization, and program subscription flows so gRPC requests always set from_slot using the chain-slot-derived value.
• Simplified gRPC client behavior now that all gRPC providers are considered backfill-capable from the caller’s perspective.
• Cleaned up stale provider-specific wording and regression tests around optional/missing from_slot behavior.

Summary by CodeRabbit

• Breaking Changes

  • gRPC endpoints now require explicit API key validation instead of relying on endpoint allowlists.

• Refactor

  • Simplified chain slot and backfill initialization by removing optional configurations. Chain slot tracking is now always required, and backfill support is now unconditionally enabled across all provider implementations.

[github-actions]

Manual Deploy Available

You can trigger a manual deploy of this PR branch to testnet:

Deploy to Testnet 🚀

Alternative: Comment /deploy on this PR to trigger deployment directly.

⚠️ Note: Manual deploy requires authorization. Only authorized users can trigger deployments.

Comment updated automatically when the PR is synchronized.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: ASSERTIVE

Plan: Pro

Run ID: db9af0d5-7475-42c5-8d15-bc2fc128e1e4

📥 Commits

Reviewing files that changed from the base of the PR and between 5c82aa5 and eec4133.

📒 Files selected for processing (7)

• magicblock-chainlink/src/remote_account_provider/chain_laser_actor/actor.rs
• magicblock-chainlink/src/remote_account_provider/chain_laser_actor/stream_manager.rs
• magicblock-chainlink/src/remote_account_provider/chain_laser_client.rs
• magicblock-chainlink/src/remote_account_provider/chain_slot.rs
• magicblock-chainlink/src/remote_account_provider/chain_updates_client.rs
• magicblock-chainlink/src/remote_account_provider/endpoint.rs
• magicblock-chainlink/src/remote_account_provider/errors.rs

💤 Files with no reviewable changes (1)

• magicblock-chainlink/src/remote_account_provider/errors.rs

---

📝 Walkthrough

Walkthrough

This PR refactors the remote account provider to eliminate optional backfill capability tracking. Endpoint::Grpc now requires an api_key field instead of storing supports_backfill, and endpoint validation requires the API key to be present. ChainSlot::compute_from_slot returns a mandatory u64 instead of Option<u64>. StreamManager now requires a non-optional ChainSlot and all from_slot parameters are mandatory u64 values. All gRPC subscription requests now unconditionally set from_slot to a concrete value. Error handling updates the enum to replace UnsupportedGrpcEndpoint with InvalidPubsubEndpoint.

Suggested reviewers

• snawaz
• GabrielePicco

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch thlorenz/normalize-grpc

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[GabrielePicco]

LGTM!