feat!: remove ToolboxTool in favor of using toolbox-core directly

Copybara import of the project:

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9cefcdd by Jack Wotherspoon <[email protected]>:

chore: delete toolbox_tool.py
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b2607eb by jackwotherspoon <[email protected]>:

feat: expose toolbox

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a4a0859 by Jack Wotherspoon <[email protected]>:

chore: update formatting
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070dc93 by jackwotherspoon <[email protected]>:

chore: add base toolbox tests

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ab84a0f by jackwotherspoon <[email protected]>:

chore: remove ToolboxTool

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87f4f90 by Jack Wotherspoon <[email protected]>:

chore: update formatting
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ddc1a11 by Jack Wotherspoon <[email protected]>:

chore: Update pyproject.toml
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aee173d by Jack Wotherspoon <[email protected]>:

chore: Update pyproject.toml
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22fc959 by Jack Wotherspoon <[email protected]>:

chore: Update __init__.py
COPYBARA_INTEGRATE_REVIEW=#763 from jackwotherspoon:expose-toolbox 3cb629a
PiperOrigin-RevId: 759744557

Author: jackwotherspoon