Feat(auth): Add theme toggle and adjust Back button on Login & Signup

[KhanjarSingh]

📋 Description

This PR updates the Login and Signup pages with two key UI improvements:

• Added a theme toggle button for switching between light and dark modes.
• Adjusted the Back button placement for better alignment and UX.
• Implemented a fallback route to "/" if no navigation history exists.

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🔗 Related Issue

Fixes #233

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🧩 Type of Change

• 🐛 Bug fix
• 🚀 New feature
• 🧹 Code refactor
• 📝 Documentation update
• ✅ Test addition or update
• ⚙️ Other (please describe):

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🧪 How Has This Been Tested?

• Tested manually on both desktop and mobile.
• Verified theme toggle persists correctly between pages.
• Checked Back button works in all navigation cases.

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📸 Screenshots (if applicable)

White theme desktop:-

white theme mobile :-

black theme mobile :-

black theme desktop:-

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🧠 Additional Context

This feature improves usability and accessibility for authentication pages.

[ikeshav26]

@KhanjarSingh I pulled the PR and checked it !!...
everyhting looking good but i think We need soem change for large devices ie. you had added the back button to the top left of page but i am talking about form's top left

[KhanjarSingh]

@ikeshav26 i will try that way it is like that across the pages so i applied that i will do it ur way and push u can check compare and merge i will just right away do it dont sleep :) be active 😆

[KhanjarSingh]

@ikeshav26 i have completed the changes u can check

[ikeshav26]

@ikeshav26 i have completed the changes u can check

@KhanjarSingh I will check within some time actually I am now on windows :)

[KhanjarSingh]

@ikeshav26 i have completed the changes u can check

@KhanjarSingh I will check within some time actually I am now on windows :)

@ikeshav26 demn too many gadgets :) , np take your time do review and tell asap after u move on to mac or whtever so i can fix fast :)

[ikeshav26]

@KhanjarSingh I think previous one is looking better.. What's your thoughts

[KhanjarSingh]

@ikeshav26 That was good but then that issue persist who will see on such and extreme end if ther have big screens or monitor in mobile view it both sct th same now it's ur and @MannuVilasara desicion

[ikeshav26]

@ikeshav26 That was good but then that issue persist who will see on such and extreme end if ther have big screens or monitor in mobile view it both sct th same now it's ur and @MannuVilasara desicion
@KhanjarSingh actually in your last commit when back button is on form's top left its not placed at top properly like see in screenshot fix it first. make it fixed for both login and signup page

So, at last i think its good to make the both icons properly placed on top and we will add this

[KhanjarSingh]

@ikeshav26 on it Sir 🫡

[KhanjarSingh]

@ikeshav26 is that fine or any more adjustment in any of the screen?

[ikeshav26]

@ikeshav26 is that fine or any more adjustment in any of the screen?
Now seems to be perfect!!....
We'll merge this PR soon

[KhanjarSingh]

@ikeshav26 have addressed the issues and pushed the changes u can review and merge.