feat: enable transaction status API

[wlawt]

Overview

This PR extends the base_* namespace to include transactionStatus.

The RPC call takes a TxHash and returns an Status enum.

It will be Status::Unknown if the TxHash doesn't exist. Otherwise, it'll return the latest BundleEventHistory, but mapped to a Status field.

It also includes proxying requests for external node users to one of Base's managed endpoints (i.e., mainnet/sepolia.base.org).

These are all feature flagged.

TODOs:

• Write some unit tests
• Implement status enum (unknown, pending, queued) or is just giving the full BundleHistory OK?
• Replace UUID with TxHash

[cb-heimdall]

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