[APP-5461] Add license to distribution

[carsongee]

Note

Low Risk
Packaging-only changes (adds license file to the staged plugin and tweaks manifest reporting) with minimal runtime impact beyond plugin metadata output.

Overview
The CLI plugin build step now stages LICENSE.txt alongside the wheel when producing the plugin distribution, warning if the file is missing.

The wrapper scripts’ --dr-plugin-manifest behavior is changed to return the contents of the generated manifest.json instead of an inlined templated JSON string, and the project version is bumped to 11.1.2.

^{Written by Cursor Bugbot for commit 89d2430. This will update automatically on new commits. Configure here.}

[engprod-2]

The Needs Review labels were added based on the following file changes.

Team @datarobot/applications (#applications) was assigned because of changes in files:

LICENSE.txt
bin/build-cli-plugin
datarobot-cli-plugin/dr-apps.ps1
datarobot-cli-plugin/dr-apps.sh
setup.cfg

If you think that there are some issues with ownership, please discuss with C&A domain at #sdtk slack channel and create PR to update DRCODEOWNERS\CODEOWNERS file.

[carsongee]

Related PR: datarobot-oss/cli#348

[devexp-slackbot]

Label Needs Review: Applications was removed because @damon-sava-stanley is part of Applications domain.