feat: chain synchronization protocol with batched range sync

[arunabha003]

Addressed Issues:

PR body:
Part of #8
Depends on #40

Summary

• Implement /minichain/sync/1.0.0 sync messages for status, range requests, and block batches
• Add sync callback hooks for local chain height, block lookup by height, and block apply
• Trigger automatic catch-up when a peer advertises a higher chain height
• Add batched sync requests with configurable sync_batch_size
• Add integration coverage for two-node catch-up synchronization across multiple batches

Validation

• python -m ruff check src tests
• python -m pytest

Checklist

• [x ] My PR addresses a single issue, fixes a single bug or makes a single improvement.
• [ x] My code follows the project's code style and conventions.
• [ x] If applicable, I have made corresponding changes or additions to the documentation.
• [ x] If applicable, I have made corresponding changes or additions to tests.
• [ x] My changes generate no new warnings or errors.
• [ x] I have joined the Stability Nexus's Discord server and I will share a link to this PR with the project maintainers there.
• [ x] I have read the Contribution Guidelines.
• [ x] Once I submit my PR, CodeRabbit AI will automatically review it and I will address CodeRabbit's comments.

AI Usage Disclosure

Check one of the checkboxes below:

• This PR does not contain AI-generated code at all.
• [ x] This PR contains AI-generated code. I have tested the code locally and I am responsible for it.

I have used the following AI models and tools: TODO

⚠️ AI Notice - Important!

We encourage contributors to use AI tools responsibly when creating Pull Requests. While AI can be a valuable aid, it is essential to ensure that your contributions meet the task requirements, build successfully, include relevant tests, and pass all linters. Submissions that do not meet these standards may be closed without warning to maintain the quality and integrity of the project. Please take the time to understand the changes you are proposing and their impact.

[coderabbitai]

Warning

Rate limit exceeded

@arunabha003 has exceeded the limit for the number of commits that can be reviewed per hour. Please wait 3 minutes and 28 seconds before requesting another review.

⌛ How to resolve this issue?

After the wait time has elapsed, a review can be triggered using the @coderabbitai review command as a PR comment. Alternatively, push new commits to this PR.

We recommend that you space out your commits to avoid hitting the rate limit.

🚦 How do rate limits work?

CodeRabbit enforces hourly rate limits for each developer per organization.

Our paid plans have higher rate limits than the trial, open-source and free plans. In all cases, we re-allow further reviews after a brief timeout.

Please see our FAQ for further information.

📥 Commits

Reviewing files that changed from the base of the PR and between c41261f and 984cdda.

📒 Files selected for processing (40)

• .github/workflows/ci.yml
• .gitignore
• Makefile
• README.md
• pyproject.toml
• src/minichain/__init__.py
• src/minichain/__main__.py
• src/minichain/block.py
• src/minichain/chain.py
• src/minichain/consensus.py
• src/minichain/crypto.py
• src/minichain/genesis.py
• src/minichain/mempool.py
• src/minichain/merkle.py
• src/minichain/mining.py
• src/minichain/network.py
• src/minichain/node.py
• src/minichain/serialization.py
• src/minichain/state.py
• src/minichain/storage.py
• src/minichain/transaction.py
• tests/test_block.py
• tests/test_block_gossip.py
• tests/test_chain.py
• tests/test_chain_sync.py
• tests/test_cli.py
• tests/test_consensus.py
• tests/test_crypto.py
• tests/test_genesis.py
• tests/test_mempool.py
• tests/test_merkle.py
• tests/test_mining.py
• tests/test_network.py
• tests/test_node.py
• tests/test_scaffold.py
• tests/test_serialization.py
• tests/test_state.py
• tests/test_storage.py
• tests/test_transaction.py
• tests/test_transaction_gossip.py

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment

---

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.}

[arunabha003]

Superseded by #42 Closing this PR to keep review history in one place.