Fixes #70 Updated the type annotation

[sidharth-vijayan]

Description

Fixed type annotation mismatch in TaskBuilder.add() method. The method was annotated to return None but actually returns self to enable method chaining. This inconsistency caused type checkers (mypy, pylint) to report errors and broke IDE autocompletion for chained calls.

Issue: [#70]

Changes Made

• Updated return type annotation of TaskBuilder.add() from -> None to -> "TaskBuilder" (lines 272)
• This matches the actual runtime behavior where the method returns self for method chaining

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation updated (documentation was updated and published)

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

Impact

• Before: Type checkers report errors on method chaining .add().add().add()
• After: Type checkers correctly recognize chaining as valid
• No breaking changes: This is purely a type hint correction; runtime behavior unchanged

Executed by: @sidharth-vijayan on 26/03/2026

[FernandoCelmer]

Thanks for the contribution, @sidharth-vijayan! 🎉

This fix was already merged in PR #79, so this PR ended up being a duplicate. We appreciate your effort and interest in improving the project!