fix 0xb96b maxFillSize

[pxrl]

Was accidentally set to 10k instead of 5k.

📥 Relayer Configuration Added

This PR adds a new configuration file inside the /configs directory for the relayer.

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🧪 Verification Checklist

• I have added my configuration file in the /configs directory.
• I have ensured no other files have been modified.
• I have successfully run the validation script: yarn validate-configs (Optional - this check also runs as a job in CI)