fix: output interruption after first response

[ibezgin-bc]

Problem
The Gemini CLI command was stopping early when capturing output using direct shell command substitution ($(gemini ...)), likely due to buffering issues or incomplete output capture.

Solution
Replaced the direct command substitution with a more robust approach:

Temporary file capture: Uses mktemp to create a temporary file for capturing the full output
Explicit error handling: Added proper exit code checking to distinguish between success and failure
Complete output capture: Captures both stdout and stderr (2>&1) to ensure no output is lost
Proper cleanup: Temporary files are cleaned up after use

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[leehagoodjames]

@gemini-cli /review

[gemini-cli]

I've reviewed the changes and left one suggestion to improve the robustness of the script. Overall, the change is a good improvement to fix the output interruption issue.

[sethvargo]

@leehagoodjames - I think this is actually why the CLI is hanging.