Redesign paused in debugger overlay (iOS)

[huntie]

Summary

Context

Continued review of built-in dev UI controls for iPhone Duo / wider screen devices.

Follows #58866.

Design changes

Redesign the "Paused in Debugger" overlay.

• Redesigned yellow pill control with a pause icon and "Tap to resume" over the dimmed app. Aligns with (and reuses) the floating design of the dev loading banner.
• Fix: Stack the paused banner above a loading banner while both are visible, with the loading banner left readable and tappable above the dimming. In practice this only happens alongside the disconnected banner.
• Improved UX for non-coders: Now displays "App paused in debugger", and "Tap to resume".

Notes

• The capsule, its window, placement and animations move out of the RCTDevLoadingView module into RCTDevBanner, a plain class in the same pod, which the module now owns. The paused overlay is an RCTPausedInDebuggerBanner subclass that overrides its hooks: window level, dimming, stack level, height, insets, the leading icon, the two-line text and the tap. The module's API is unchanged.
• Move RCTPausedInDebuggerOverlayController into React-CoreModules so it can reach RCTDevBanner. Its only caller, RCTHost, already depends on that pod.

Before	After

Changelog:
[iOS][Changed] - Paused in debugger overlay: Redesign as a floating capsule

Test Plan

• ✅ On the iPhone 18 Pro simulator, Debugger.pause from a scripted DevTools session shows the banner over the dimmed app, and tapping it sends Debugger.resumed and hides it.
• ✅ While paused, a tap on the app content stops at the dimming view, and the disconnected banner's dismiss button above it still takes the touch and dismisses it.
• ✅ With the disconnected banner shown, the paused banner stays on top and the disconnected banner sits 12pt below it.

Paused, iPhone 18 Pro

Light	Dark

Edge case: Paused with the disconnected banner

Light	Dark

• ✅ Now stacks both indicators
  • Note: Fast Refresh/Loading will never clash with Paused in Debugger. The only theoretical stack is Paused + Disconnected from dev server.
• ✅ Dismiss button on disconnected banner still receives tap

[github-actions]

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