fix(cli): fix help message starting with Error:

[Molter73]

Description

While testing #110, I realised when running fact with --help the usage message would start with the Error: string, like this:

Error: Usage: fact [OPTIONS] [URL]

This is due to us incorrectly using the try_parse method on our CLI configuration and propagating the error up. Instead, we can call parse and the application will come to a full stop whenever a wrong argument is found or the -h or --help arguments are provided, showing the correct usage message.

The change also makes it so configuration is parsed before dumping system information. This is more of a nitpick, having the system information dumped before the usage message is not a big deal, but I think this way makes more sense. Additionally, errors parsing configuration and CLI arguments should not be caused by the actual system, so I don't think we are losing anything.

Checklist

• Investigated and inspected CI test results
• Updated documentation accordingly

Automated testing

• Added unit tests
• Added integration tests
• Added regression tests

If any of these don't apply, please comment below.

Testing Performed

Manually run cargo run -- -h before the change:

   Compiling fact v0.2.0-dev (/home/mmoltras/go/src/github.com/molter73/fact/fact)
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 4.07s
     Running `target/debug/fact -h`
[INFO  2025-10-17T08:40:46Z] fact version: 0.1.x-69-g27fe4c5074
[INFO  2025-10-17T08:40:46Z] OS: Fedora Linux 42 (Workstation Edition)
[INFO  2025-10-17T08:40:46Z] Kernel version: 6.16.10-200.fc42.x86_64
[INFO  2025-10-17T08:40:46Z] Architecture: x86_64
[INFO  2025-10-17T08:40:46Z] Hostname: mmoltras-thinkpadp1gen5.remote.csb
Error: Usage: fact [OPTIONS] [URL]

Arguments:
  [URL]  URL to forward the packages to [env: FACT_URL=]

Options:
  -p, --paths [<PATHS>...]           List of paths to be monitored [env: FACT_PATHS=]
  -c, --certs <CERTS>                Directory holding the mTLS certificates and keys [env: FACT_CERTS=]
  -e, --endpoint <ENDPOINT>          The port to bind for all exposed endpoints [env: FACT_ENDPOINT=]
      --expose-metrics               Whether prometheus metrics should be collected and exposed [env: FACT_EXPOSE_METRICS=]
      --health-check                 Whether a small health_check probe should be run [env: FACT_HEALTH_CHECK=]
      --skip-pre-flight              Whether to perform a pre flight check [env: FACT_SKIP_PRE_FLIGHT=]
  -j, --json                         Force events to be output as JSON to stdout [env: FACT_JSON=]
  -r, --ringbuf-size <RINGBUF_SIZE>  Sets the size of the ringbuffer to be used in kilobytes [env: FACT_RINGBUF_SIZE=]
  -h, --help                         Print help (see more with '--help')
  -V, --version                      Print version

After the change:

   Compiling fact v0.2.0-dev (/home/mmoltras/go/src/github.com/molter73/fact/fact)
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 5.35s
     Running `target/debug/fact -h`
Usage: fact [OPTIONS] [URL]

Arguments:
  [URL]  URL to forward the packages to [env: FACT_URL=]

Options:
  -p, --paths [<PATHS>...]           List of paths to be monitored [env: FACT_PATHS=]
  -c, --certs <CERTS>                Directory holding the mTLS certificates and keys [env: FACT_CERTS=]
  -e, --endpoint <ENDPOINT>          The port to bind for all exposed endpoints [env: FACT_ENDPOINT=]
      --expose-metrics               Whether prometheus metrics should be collected and exposed [env: FACT_EXPOSE_METRICS=]
      --health-check                 Whether a small health_check probe should be run [env: FACT_HEALTH_CHECK=]
      --skip-pre-flight              Whether to perform a pre flight check [env: FACT_SKIP_PRE_FLIGHT=]
  -j, --json                         Force events to be output as JSON to stdout [env: FACT_JSON=]
  -r, --ringbuf-size <RINGBUF_SIZE>  Sets the size of the ringbuffer to be used in kilobytes [env: FACT_RINGBUF_SIZE=]
  -h, --help                         Print help (see more with '--help')
  -V, --version                      Print version