🔒 Secure web intents using Custom Tabs

[LeanBitLab]

🎯 What: This PR fixes a security vulnerability where several web URLs were opened using implicit Intent.ACTION_VIEW intents.

⚠️ Risk: Implicit intents for common actions like viewing web pages can be intercepted by any application that registers a matching intent filter. A malicious app could intercept these intents, leading to a degraded user experience, phishing attempts, or unintended exposure of parameters if they were present.

🛡️ Solution:

1. Added the androidx.browser:browser dependency to app/build.gradle.kts.
2. Replaced Intent(Intent.ACTION_VIEW, ...) with CustomTabsIntent.Builder().build().launchUrl(...) for all http:// and https:// links in MainActivity.kt.
3. Kept market:// links as standard intents to allow handling by installed app stores (like Google Play).

This ensures that web links open securely within a Chrome Custom Tab, or the default configured browser, protecting the user from intent interception attacks.

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PR created automatically by Jules for task 11572267991238799803 started by @LeanBitLab

[google-labs-jules]

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