[Python] fix constraint settings for decimalType

[Mattias-Sehlstedt]

Fixes Python constraints where less than and greater than were inverted.

PR checklist

• Read the contribution guidelines.
• Run the following to build the project and update samples:

  ./mvnw clean package || exit
  ./bin/generate-samples.sh ./bin/configs/*.yaml || exit
  ./bin/utils/export_docs_generators.sh || exit
  

  (For Windows users, please run the script in WSL)
  Commit all changed files.
  This is important, as CI jobs will verify all generator outputs of your HEAD commit as it would merge with master.
  These must match the expectations made by your contribution.
  You may regenerate an individual generator by passing the relevant config(s) as an argument to the script, for example ./bin/generate-samples.sh bin/configs/java*.
  IMPORTANT: Do NOT purge/delete any folders/files (e.g. tests) when regenerating the samples as manually written tests may be removed.
• If your PR is targeting a particular programming language, @mention the technical committee members, so they are more likely to review the pull request.

cc @taxpon (2017/07) @frol (2017/07) @mbohlool (2017/07) @cbornet (2017/09) @kenjones-cisco (2017/11) @tomplus (2018/10) @arun-nalla (2019/11)

---

Summary by cubic

Fixes inverted numeric constraints for Python decimal fields and unifies constraint handling across numeric types. Adds tests to verify correct pydantic Field parameters for integers, numbers, doubles, and decimals.

• Bug Fixes

  • Correctly map Decimal constraints: exclusiveMinimum → gt, exclusiveMaximum → lt, minimum → ge, maximum → le.
  • Added unit test using format.yaml to assert expected Field(...) annotations, including decimal.

• Refactors

  • Introduced shared applyConstraints for numeric types (int, decimal) and standardized imports via PYDANTIC/TYPING constants.
  • Validated mapNumberTo against a supported set and improved the error message for invalid values.

^{Written for commit 29d63a2. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 3 files

_{Re-trigger cubic}

[wing328]

lgtm. thanks for the fix