fix: improve Toast and add InAppBrowser dark mode for V2EX

[graycreate]

Summary

• Fix Toast shadow being too dark
• Fix Toast not clearing issue when appearing consecutively
• Add automatic dark mode support for V2EX pages in InAppBrowser

Changes

Toast Improvements

• Reduce shadow opacity from 0.3 to 0.12 for a softer, less aggressive appearance
• Add version property to track toast updates
• Reset dismiss timer when new toast content arrives (even if isPresented stays true)

InAppBrowser Dark Mode

• Inject dark mode CSS for V2EX and v2er.app pages when app is in dark mode
• Auto-detect app's appearance setting (dark/light/system)
• Comprehensive styling: boxes, cells, headers, links, code blocks, inputs

Test plan

• Show multiple toasts in quick succession - verify each one appears and dismisses correctly
• Verify toast shadow is lighter/softer
• Enable dark mode in app settings
• Open a V2EX link in InAppBrowser - verify dark theme is applied
• Switch to light mode - verify V2EX pages show light theme

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR improves the Toast component's visual design and consecutive display handling, while also adding automatic dark mode CSS injection for V2EX pages in the InAppBrowser.

Key Changes:

• Toast shadow made lighter (opacity 0.3 → 0.12) with improved positioning for a softer appearance
• Added version tracking to properly reset toast timers when consecutive toasts appear with the same isPresented state
• Implemented dark mode CSS injection for V2EX and v2er.app domains when the app is in dark mode

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
V2er/View/Widget/Toast.swift	Added version property to track toast updates and trigger timer resets; updated shadow for softer appearance
V2er/State/DataFlow/Actions/GlobalActions.swift	Increment toast version on each ShowToastAction to ensure onChange handlers detect new toasts
V2er/View/Login/LoginPage.swift	Pass toast version to the toast view modifier to enable timer reset functionality
V2er/General/RootView.swift	Pass toast version to the toast view modifier to enable timer reset functionality
V2er/View/InAppBrowserView.swift	Added dark mode detection and CSS injection for V2EX pages in the InAppBrowser

[Copilot]

The CSS string is embedded in a JavaScript template literal using string interpolation. While the current hardcoded CSS is safe, this pattern is fragile—if the CSS string ever contains backticks (`) or template literal expressions (${...}), it could break the JavaScript or create an injection vulnerability. Consider using proper escaping or a safer injection method, such as replacing backticks with escaped backticks in the CSS string before interpolation.

Suggested change

	let js = "var style = document.createElement('style'); style.innerHTML = `\(darkModeCSS)`; document.head.appendChild(style);"
	let safeDarkModeCSS = darkModeCSS
	.replacingOccurrences(of: "\\", with: "\\\\")
	.replacingOccurrences(of: "`", with: "\\`")
	.replacingOccurrences(of: "${", with: "\\${")
	let js = "var style = document.createElement('style'); style.innerHTML = `\(safeDarkModeCSS)`; document.head.appendChild(style);"

[Copilot]

Dark mode CSS is injected on every page load completion without checking if it was already injected. This could result in duplicate style tags if a page reloads or navigates within the same webView. Consider checking if the styles are already present or using a unique ID on the style tag to prevent duplicates.

Suggested change

	let js = "var style = document.createElement('style'); style.innerHTML = `\(darkModeCSS)`; document.head.appendChild(style);"
	let js = """
	if (!document.getElementById('v2er-dark-mode-style')) {
	var style = document.createElement('style');
	style.id = 'v2er-dark-mode-style';
	style.innerHTML = `\(darkModeCSS)`;
	document.head.appendChild(style);
	}
	"""

[github-actions]

Code Coverage Report ❌

Current coverage: 30.24%

[github-actions]

Code Coverage Report ❌

Current coverage: 31.01%