Describe the feature

We need to implement a trie cursor interface that allows seeking and iterating over trie nodes stored in the historical proof database. This cursor will enable building proofs efficiently for both account and storage tries at any given block.

Goals:

• Implement trie_cursor method
• Implement the ExternalTrieCursor trait

Acceptance Criteria:

• Cursor supports iteration over account and storage trie nodes efficiently.
• seek and seek_exact correctly handle lexicographical ordering of trie paths.
• Cursor respects max_block_number to return the state as of a given block.
• Unit tests validate correct traversal, seek behavior, and handling of edge cases.

Additional context

No response