🔒 Fix unquoted variable expansion in convert_pdfs.sh

[dynamikdev]

🎯 What: Fixed an unquoted variable expansion vulnerability in scripts/convert_pdfs.sh line 26 by changing echo $num to echo "$num".
⚠️ Risk: Unquoted variable expansions inside commands like echo are subject to shell word-splitting and globbing. If the num variable contained space characters or wildcard characters (like * or ?), it could lead to unexpected behavior or potential command injection vulnerabilities. While the immediate context extracts numbers, quoting is a required defensive programming practice in bash.
🛡️ Solution: Added double quotes around the $num variable in the echo command clean_num=$(echo "$num" | sed 's/^0*//'), completely mitigating the risk of word-splitting and globbing. Verified script execution and bash syntax check.

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PR created automatically by Jules for task 9219451036217171693 started by @dynamikdev

[google-labs-jules]

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