Adapt Sedge to handle the current keystore format used by Charon

[boulder225]

🎯 Problem to be solved

Sedge expects a specific keystore directory structure to import keys, which is different from the structure used by Charon. See: NethermindEth#368

It appears that the import process is working fine, but the provided keystore directory structure is not correct

🛠️ Proposed solution

• Manually test the key import process by restructuring the keystore directory to match Sedge's expected format
• If the manual test is successful, update Sedge to handle the current keystore format used by Charon
• Alternatively, if the manual test fails, investigate and address any underlying issues with the key import process

[boulder225]

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