Use rustyline's termios backend - #37

control: job assigned to worker 01KZV8A6D9JYR3DF6M13T7C1T9 [factory aws, i-050b892618b4e8981] (queued for 54 s)
...
task: starting task 0: "setup"
task: process exited: duration 4082 ms, exit code 0
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task: starting task 1: "rust-toolchain"
task: process exited: duration 17128 ms, exit code 0
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task: starting task 2: "authentication"
task: process exited: duration 16 ms, exit code 0
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task: starting task 3: "clone repository"
task: process exited: duration 1125 ms, exit code 0
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task: starting task 4: "build"
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|    Compiling shlex v1.3.0
|    Compiling xdg v3.0.0
|    Compiling tokio-rustls v0.26.4
|    Compiling rustls-platform-verifier v0.7.0
|    Compiling hyper-rustls v0.27.9
|    Compiling reqwest v0.13.4
|    Compiling progenitor-client v0.14.0
|    Compiling progenitor v0.14.0
|    Compiling oauth2-reqwest v0.1.0-alpha.3
|    Compiling sush-api v0.1.0 (/work/oxidecomputer/sush/api)
|    Compiling permission-slip-client v1.1.0 (https://github.com/oxidecomputer/permission-sl [...]
|    Compiling sush-client v0.1.0 (/work/oxidecomputer/sush/client)
|     Finished `release` profile [optimized] target(s) in 2m 03s
| warning: the following packages contain code that will be rejected by a future version of  [...]
| note: to see what the problems were, use the option `--future-incompat-report`, or run `ca [...]
| + cp target/release/sush /work/sush
task: process exited: duration 124343 ms, exit code 0
|W| found 1 output files
|W| uploading: /work/sush (37718936 bytes)
|W| uploaded: /work/sush