feat: Bitswap Py-cid migration Phase 3

[ItshMoh]

Issue #1246

Summary

It applies shared CID normalization helpers across Bitswap modules and example flows so mixed CID input types are accepted at boundaries, while keeping current byte-based wire/storage behavior stable.

work done

• libp2p/bitswap/block_store.py

  • Store APIs now accept CIDInput and normalize with cid_to_bytes(...).
  • Internal key type remains bytes.

• libp2p/bitswap/messages.py

  • Wantlist/block-presence helpers accept CIDInput.
  • Protobuf CID fields are normalized to bytes before assignment.

• libp2p/bitswap/client.py

  • Public methods (add_block, get_block, want_block, have_block, cancel_want) accept CIDInput.
  • Input normalization is applied once at entry and normalized bytes are used consistently for internal maps and messaging paths.

• libp2p/bitswap/dag.py

  • fetch_file(...) and get_file_info(...) accept CIDInput and normalize at entry.

• libp2p/bitswap/dag_pb.py

  • Link accepts CIDInput and normalizes non-byte inputs.
  • Raw bytes remain accepted as-is for backward compatibility.
  • create_file_node(...) / create_directory_node(...) support mixed CID input tuples.

Logging / text representation

• Replaced runtime CID .hex() usage in migrated paths with canonical CID text display where appropriate.
• Preserved safe hex fallback behavior for malformed/unparseable bytes.

Example CLI migration

• examples/bitswap/bitswap.py
  • --cid now accepts canonical CID text, /ipfs/... form, and hex fallback.
  • CID display is canonical-text-first.
  • Help text updated to reflect accepted formats.

[ItshMoh]

Here the ci fail is flaky, I ran the failing test test_swarm_conn.py locally and it passed. the most probable cause is that this test uses trio.sleep(0.01) waits and it can be short on loaded CI workers, especially with -n auto.