feat(coprocessor): add log level configurations

[dartdart26]

Add the log-level cmd line option to configure the log level.

Also, make sure gw-listener and transaction-sender retry connecting to the node infinitely at startup as the WsConnect options don't apply to connect during provider creation.

Finally, add structured logging to fhevm-listener instead of println!s. Also, added some TODOs to remove panics and, instead, propagate errors. Will be done in a separate PR.

As a side note, using structured logging in all other services where it is applicable will be done in a separate PR as well (as we usually only utilize the message field in the log macros).

Resolves https://github.com/zama-ai/fhevm-internal/issues/88

[Copilot]

Pull Request Overview

This PR introduces a --log-level option for configuring log verbosity, switches WebSocket connection retries to indefinite loops with logging, and replaces ad-hoc println!/eprintln! calls in the fhevm-listener service with structured tracing macros.

• Added log_level: Level to CLI args and propagated it into tracing_subscriber setup.
• Changed get_chain_id to retry indefinitely with logged errors.
• Replaced all println!/eprintln! in fhevm-listener with info!, warn!, and error!.

Reviewed Changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
transaction-sender/tests/common.rs	Simplified get_chain_id invocation in tests.
transaction-sender/src/lib.rs	Removed retry params, implemented infinite retry with logs.
sns-executor/src/lib.rs	Added log_level field to Config.
fhevm-listener/src/cmd/mod.rs	Introduced log_level CLI arg and structured logging.
fhevm-listener/Cargo.toml	Added tracing and tracing-subscriber dependencies.
coprocessor/src/lib.rs (async_main)	Passed args.log_level into tracing_subscriber.
coprocessor/src/daemon_cli.rs	Added log_level to daemon CLI args.

Comments suppressed due to low confidence (1)

coprocessor/fhevm-engine/transaction-sender/src/lib.rs:93

• [nitpick] Use Rust doc comments (///) instead of // so these lines appear in generated docs and IDE tooltips.

// Gets the chain ID from the given WebSocket URL.