[FEATURE] Add IP/Subnet calculator tool to Standalone Tools

[NovaCode37]

PRISM has a "Standalone Tools" section. An IP/Subnet Calculator is a essential daily tool for security engineers and network admins to calculate network ranges, CIDR, wildcard masks, and usable hosts.

Let's add this as a simple, interactive React-only tool.

What to do

1. Create a new component or add to existing standalone tools in the frontend.
2. Input: IP Address (e.g., 192.168.1.1) and Subnet Mask/CIDR (e.g., /24 or 255.255.255.0).
3. Output:
   • CIDR notation
   • Network address
   • Broadcast address
   • First usable IP
   • Last usable IP
   • Total usable hosts
4. Build this purely in React (no backend calls needed, there are simple pure-JS subnet math algorithms or packages, but vanilla JS is preferred to keep bundle size small).

Acceptance criteria

• Interactive UI with input validation (checks if IP is valid).
• Instantly calculates network details.
• Matches the modern, dark-themed UI of the PRISM platform.

[githubuser16384]

Hi @NovaCode37,
I have gone through this issue and would like to contribute to the same. Kindly assign the issue to me.

[NovaCode37]

Hi @NovaCode37, I have gone through this issue and would like to contribute to the same. Kindly assign the issue to me.

Yep, assigned it to you