Add Swift Package Manager support (Core + UI + WebP)

[damian-kolasinski]

Summary

Adds Swift Package Manager support so the library can be consumed via SPM instead of CocoaPods. The package exposes a single DFImageManager library product covering the Core, UI and WebP subspecs (the set the KingsChat app uses). AFNetworking, GIF and PhotosKit subspecs are excluded.

What changed

• Package.swift — swift-tools-version 5.9, platform iOS 15, one target rooted at Pod/Source.
• Pod/Source/include/DFImageManager/ — symlinks to all public headers (Core public + UI + WebP), so consumers keep using #import <DFImageManager/...> exactly as with the CocoaPods framework. Symlinks (the same pattern libwebp-Xcode uses) avoid duplicate-header drift and keep quoted intra-target imports working.
• Pod/Source/include/module.modulemap — custom module map declaring umbrella "DFImageManager". Without it, SPM auto-picks DFImageManager.h as the sole umbrella header (name matches the module) and the rest of the API disappears from the module.
• WebP — the libwebp/webp pod dependency is replaced with the maintained SPM wrapper SDWebImage/libwebp-Xcode pinned at exact 1.3.2 (same libwebp version as the pod). DFWebPImageDecoder.m now imports <webp/decode.h> (also resolves under CocoaPods).
• DF_SUBSPEC_WEBP_ENABLED=1 is defined target-wide via cSettings, matching the merged prefix header CocoaPods generates when the WebP subspec is active — DFImageManager.sharedManager still registers DFWebPImageDecoder and sends the image/webp Accept header.

The podspec is untouched; CocoaPods consumption of this repo keeps working.

Consuming

There are no tags on this fork — pin by revision:

.package(url: "https://github.com/appunite/DFImageManager.git", revision: "7c024548b819dc59a4f15e5fc06d1353c63ea11b")

Product/target name: DFImageManager.

Validation

• xcodebuild -scheme DFImageManager -destination "generic/platform=iOS Simulator" build — succeeds (only pre-existing OSSpinLock deprecation warnings).
• A throwaway consumer package importing every <DFImageManager/...> header the KingsChat app uses (plus @import DFImageManager;, DFImageRequest, DFWebPImageDecoder, DFImageManager.sharedManager) builds clean for iOS Simulator from a wiped DerivedData.
• The compiled object exposes the DFWebPImageDecoder symbols and the compile flags include DF_SUBSPEC_WEBP_ENABLED=1.

https://claude.ai/code/session_01LTj6vGgu7NmTs7bjupWAGh