refactor(api): trim over-engineered scaling, fast-path, and SwiftUI surface

[Dicky019]

Summary

Removes redundant and speculative public API across the scaling, fast-path, debug, and SwiftUI layers, reducing ScreenUtil to its cross-platform scaling primitives plus the platform ergonomics that carry real logic. Driven by a multi-lens audit (over-engineering, clean-code, SOLID, Swift-concurrency, SwiftUI/UIKit). Net −733 lines (253 insertions, 986 deletions) across 24 files, with no behavior change to the surviving API.

⚠️ Breaking change — public API removed. Acceptable pre-v1.0 (not yet released). See Migration below.

What changed

Scaling

• Numeric+Scaling: 4 copy-paste Int/Float/Double/CGFloat extensions → 2 generics (BinaryInteger, BinaryFloatingPoint) — also covers Int64/UInt uniformly, closing the silent-scale-to-zero gap.
• Removed the per-value .fastW/.fastH/.fastSp numeric variants (~1.1× over .w/.h/.sp, not the documented speedup). The real hot-loop path — FastScale / withFastScale — is unchanged.
• FastScale now delegates to the internal ScaleFactorCache core instead of re-implementing the capture.
• Consolidated batch scaling onto BatchScaler (added scale/points/rects); dropped the redundant, drifted ScreenUtil.batch* methods.

Debug

• ScreenUtilDebug struct+singleton → caseless enum of static methods; dropped validateScaling, generateTestReport, and the free-function wrappers.

SwiftUI

• Removed Font.scaledSystem/scaledCustom, @ScaledValue/@ScreenPercentage, and the responsiveFrame/responsivePadding/responsiveCornerRadius view modifiers — all thin sugar over the .w/.h/.sp/.r primitives applied inside native modifiers. Kept EnvironmentValues.screenUtil (file renamed to Environment+ScreenUtil.swift).

Bug fixes (included)

• responsivePadding(.all) scaled every edge by height only — fixed to scale each axis by its own factor (now applied at consumer call sites).
• UIView constraint helpers now disable the autoresizing mask and batch-activate constraints.

Docs / examples / tests

Updated to the new surface; stale CLAUDE.md "Known Issues" (data race, stale-on-rotation — both already fixed in source) struck.

Migration

Removed	Use instead
100.fastW / .fastH / .fastSp	100.w / .h / .sp (or FastScale in a hot loop)
ScreenUtil.shared.batchWidths(xs)	ScreenUtil.shared.batchScaler.widths(xs)
.font(.scaledSystem(size: 16))	.font(.system(size: 16.sp))
@ScaledValue(.width) var w = 100	let w = 100.w
.responsiveFrame(width: 200, height: 50)	.frame(width: 200.w, height: 50.h)
ScreenUtilDebug.shared.printCurrentConfiguration()	ScreenUtilDebug.printCurrentConfiguration()

Verification

• swift build clean under -strict-concurrency=complete, no new warnings.
• swift test: 105 tests, 0 failures (down from 116 — removed tests covered deleted API; no behavioral coverage lost).
• UIKit-only helpers are build-verified on the CI iOS job (not compiled on the macOS test host).

Commits

• refactor(api): trim over-engineered scaling and SwiftUI convenience surface
• refactor(scaling): remove .fastW/.fastH/.fastSp numeric variants
• docs(scaling): drop removed .fast* numeric API from docs