feat(tvix/store/bin): add progress bar infrastructure

This adds the tracing-indicatif crate, and configures it as a layer in
our tracing_subscriber pipeline to emit progress for every span that's
configured so.

It also moves from using std::io::stderr to write logs to using their
writer, to avoid clobbering output.

Progress bar styles are defined in a lazy_static, moving this into a
general tracing is left for later.

This adds some usage of this to the `imports` and `copy` commands.

The output can still be improved a bit - we should  probably split each
task up into a smaller (instrumented) helper functions, so we can create
a progress bar for each task.

Change-Id: I59a1915aa4e0caa89c911632dec59c4cbeba1b89
Reviewed-on: https://cl.tvl.fyi/c/depot/+/11747
Reviewed-by: flokli <flokli@flokli.de>
Reviewed-by: Simon Hauser <simon.hauser@helsinki-systems.de>
Tested-by: BuildkiteCI
Autosubmit: flokli <flokli@flokli.de>

tvix/store/Cargo.toml

@@ -43,6 +43,8 @@ walkdir = "2.4.0"
 reqwest = { version = "0.11.22", features = ["rustls-tls-native-roots", "stream"], default-features = false }
 lru = "0.12.3"
 parking_lot = "0.12.2"
+indicatif = "0.17.8"
+tracing-indicatif = "0.3.6"
 
 [dependencies.tonic-reflection]
 optional = true