Document technical limitations of shell instrumentation

[Copilot]

• Research and understand the limitations mentioned in the issue
• Identify the appropriate location in README.md for the limitations section
• Document the limitation: Functions without the function keyword whose names collide with real commands
• Document the limitation: File descriptor conflicts (magic file descriptor 7)
• Document the limitation: PID tracking issues when commands become functions
• Review and refine documentation
• Ensure documentation is clear and detailed but not overly prominent
• Address feedback: Move shell functions and absolute paths to 1st and 2nd place as separate sections
• Address feedback: Note shell functions as "by design"
• Address feedback: Move PID tracking to last position

Original prompt

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This section details on the original issue you should resolve

<issue_title>Document limitations</issue_title>
<issue_description>functions without function keyword whos names colide with real commands
exec file descriptor fuckery
magic filedescriptor used
saving pid and killing command kills subshell, not command because now its a function, not an external command</issue_description>

<agent_instructions>add a limitations section at an appropriate but not too prominent location in the readme and talk about these items in detail</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Document limitations #2809

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[plengauer]

@copilot pls address

[Copilot]

@copilot pls address

Both review comments have been addressed in commit 06921b8.

[Copilot]

Pull request overview

This PR adds a comprehensive "Limitations" section to the README documenting technical constraints of the shell instrumentation system. The changes address issue #2809 by explaining scenarios where automatic instrumentation doesn't work or has known issues, along with workarounds for each limitation.

Changes:

• Expanded the existing single-line "Limitations" section into a detailed subsection with 6 documented limitations
• Added explanations of technical constraints including shell functions, path-based commands, file descriptor conflicts, restricted mode, and PID tracking
• Provided workarounds for each limitation where applicable