🔒 Fix Command Injection via Unescaped User Input in Network Config

[WHYCRASH]

🎯 What:
Fixed a vulnerability in pre-install-wizard.sh where user-provided Wi-Fi credentials were included in an initramfs.conf file without escaping.

⚠️ Risk:
If an attacker provides malicious input (e.g. test" } evil_network={ ssid="hacked" } ) into the WIFI_SSID or WIFI_PASS prompts, they could inject arbitrary configuration directives into the wpa_supplicant config file, allowing command execution or unauthorized network manipulation.

🛡️ Solution:
Added safe parameter expansion mapping to escape backslashes and double quotes in the WIFI_SSID and WIFI_PASS variables before interpolating them into the heredoc, ensuring user inputs are treated solely as literal strings within the network config block.

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PR created automatically by Jules for task 16445463733097985311 started by @WHYCRASH

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