Remove all runtime panics from the code

[hbjydev]

Currently, if the worker services run into any failures, they just panic their guts into stdout/stderr:

thread 'tokio-runtime-worker' panicked at cli/src/command/start/agent.rs:332:14:
failed to push: Status { code: Internal, message: "failed to write store path: Os { code: 2, kind: NotFound, message: \"No such file or directory\" }", metadata: MetadataMap { headers: {"content-type": "application/grpc", "date": "Fri, 23 May 2025 16:53:17 GMT"} }, source: None }
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
thread 'tokio-runtime-worker' panicked at cli/src/command/start/agent.rs:332:14:
failed to push: Status { code: Internal, message: "failed to write store path: Os { code: 2, kind: NotFound, message: \"No such file or directory\" }", metadata: MetadataMap { headers: {"content-type": "application/grpc", "date": "Fri, 23 May 2025 16:53:43 GMT"} }, source: None }
thread 'tokio-runtime-worker' panicked at cli/src/command/start/agent.rs:332:14:
failed to push: Status { code: Internal, message: "failed to write store path: Os { code: 2, kind: NotFound, message: \"No such file or directory\" }", metadata: MetadataMap { headers: {"content-type": "application/grpc", "date": "Fri, 23 May 2025 16:53:56 GMT"} }, source: None }

This should probably be using tracing::error!() with some kind of Result handling instead, because anyhow::bail!(...) just seems to panic outright.