Create venv_linux virtual environment and record it in TASK.md

[brothercorvo]

Motivation

• Provide a consistent virtual environment for running Python commands and tests as required by the project guidelines.
• Record progress in the project task list so the setup step is tracked in TASK.md.

Description

• Create the venv_linux virtual environment using python3 -m venv venv_linux.
• Update TASK.md to mark the venv_linux environment as created.
• No other code logic or API changes were introduced in this change.

Testing

• No automated tests were run for this change.

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Codex Task