fix: correct file path handling for PDF generation

[lightning-sagar]

Description

• Fixed PDF generation issue on Windows by normalizing file paths.
• Converted backslashes (\) to forward slashes (/) and prepended file:/// to create a valid file URL for Puppeteer.
• Ensures PDF generation works cross-platform (Windows, macOS, Linux).

Related issue(s)
Fixes #755

[lightning-sagar]

Note: The JS/CSS files will not be generated yet. This will be addressed once the default value issue is resolved. The related PR has already been created: #1769

Edit - in new commit, i replaced replace(/\\/g, '/') with replaceAll('\\', '/') to satisfy SonarCloud

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[derberg]

/rtm