Guidelines / solution to run compiled version

[vkammerer]

Is your feature request related to a problem? Please describe.
The current execution of flutter pub run import_sorter:main has a slow start due to the Dart VM initialisation. While it is acceptable if it is ran infrequently (like as a GIT commit hook for example), it is a lot more critical when running frequently (like every time a file is saved for example).

Describe the solution you'd like

• Give users guidelines to use the natively compiled version of the library rather that its Dart version
• OR find a way to distribute the compiled versions

Describe alternatives you've considered
I have tested the execution time of this library for three different versions:

• 1: The Dart version, as described in the README
• 2: The AOT compiled version, as described in https://dart.dev/tools/dart-compile#aot-snapshot
• 3: The executable compiled version, as described in https://dart.dev/tools/dart-compile#exe

Results:

• 1 was the slowest, with an initialisation time of about 1 to 2 seconds on a i9 2019 Macbook Pro 16'.
• 2 was faster, maybe twice faster.
• 3 was the fastest, almost instantaneous

Additional context
The benefits of running a compiled version are also explained in https://dart.dev/tutorials/server/get-started#6-compile-for-production.

This is what I've done to get a nice experience using this lib:

1. Compile to native code

dart compile exe bin/main.dart -o bin/import_sorter

2. Add bin path to PATH
3. Use lib in VSCode with https://marketplace.visualstudio.com/items?itemName=emeraldwalk.RunOnSave
   I've set it up with the following settings:

  "emeraldwalk.runonsave": {
    "commands": [
      {
        "match": "\\.dart$",
        "cmd": "import_sorter ${file}"
      }
    ]
  }

Now every time I save a file in my IDE, the imports are organised instantaneously! This makes it a lot more enjoyable.

[gleich]

See #63