Refactor scripts for improved variable quoting and consistency

[vncloudsco]

• Updated variable references to use double quotes for better safety and consistency across deploy.sh, install-nginx-modsecurity.sh, quickstart.sh, and start.sh.
• Enhanced readability by ensuring uniformity in variable usage.

[Copilot]

Pull Request Overview

This PR refactors shell scripts to improve variable quoting consistency and safety by wrapping variable references in double quotes. The changes enhance protection against word splitting and pathname expansion issues that can occur with unquoted variables in bash.

• Updated all variable references to use double quotes ("${VAR}" instead of $VAR)
• Applied consistent quoting patterns across deploy.sh, install-nginx-modsecurity.sh, quickstart.sh, and start.sh
• Maintained script functionality while improving robustness

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
scripts/start.sh	Updated variable references to use double quotes for paths, PIDs, and process handling
scripts/quickstart.sh	Applied consistent double quoting to database configuration, Docker commands, and process variables
scripts/install-nginx-modsecurity.sh	Enhanced variable quoting in logging, configuration paths, and system commands
scripts/deploy.sh	Standardized variable quoting for database setup, service configuration, and deployment parameters

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[sonarqubecloud]

Quality Gate failed

Failed conditions
25.2% Duplication on New Code (required ≤ 3%)

See analysis details on SonarQube Cloud