Rewrite file viewer with pinned gutter, syntax highlighting, and toolbar

Replace the SwiftUI-only CodeFileTextView with a UIViewRepresentable backed
by CodeFileUIView. The previous approach could not support a fixed line number
gutter while independently scrolling code content horizontally.

Changes:
- Gutter is pinned outside the horizontal scroll view and never scrolls left
- Vertical scroll is handled by a single outer UIScrollView shared by both
  the gutter and code content, keeping them in sync
- Line numbers are right-aligned in a fixed-width gutter calculated from
  the total line count
- Syntax highlighting via Splash for .swift files, with plain monospaced
  rendering as fallback for unsupported file types
- Wrap toggle persisted via AppStorage (wrapRepositoryFileLines)
- Bottom toolbar replaces the floating Share button, adding Copy All and
  Wrap toggle actions
- Copy All shows a brief checkmark confirmation that resets after 2 seconds
- Font fixed at SFMono-Regular 12pt, not scaled with Dynamic Type

Implements: https://todo.sr.ht/~ccleberg/Hutch/7

2 files changed, 27 insertions, 1 deletions

diff --git a/Hutch.xcodeproj/project.pbxproj b/Hutch.xcodeproj/project.pbxproj
index cb7bea9..d844cd3 100644
--- a/Hutch.xcodeproj/project.pbxproj
+++ b/Hutch.xcodeproj/project.pbxproj
@@ -16,6 +16,7 @@
 		8BE09E812F7B2CC300F88693 /* styles.css in Resources */ = {isa = PBXBuildFile; fileRef = 8BE09E7D2F7B2CC300F88693 /* styles.css */; };
 		8BE09E822F7B2CC300F88693 /* privacy.html in Resources */ = {isa = PBXBuildFile; fileRef = 8BE09E7B2F7B2CC300F88693 /* privacy.html */; };
 		8BF100032F9A000100000001 /* Markdown in Frameworks */ = {isa = PBXBuildFile; productRef = 8BF100022F9A000100000001 /* Markdown */; };
+		8BF100052F9A000100000002 /* Splash in Frameworks */ = {isa = PBXBuildFile; productRef = 8BF100042F9A000100000002 /* Splash */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
@@ -116,6 +117,7 @@
 			buildActionMask = 2147483647;
 			files = (
 				8BF100032F9A000100000001 /* Markdown in Frameworks */,
+				8BF100052F9A000100000002 /* Splash in Frameworks */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -198,6 +200,7 @@
 			name = Hutch;
 			packageProductDependencies = (
 				8BF100022F9A000100000001 /* Markdown */,
+				8BF100042F9A000100000002 /* Splash */,
 			);
 			productName = Hutch;
 			productReference = 8B4B28D12F6704280045FA19 /* Hutch.app */;
@@ -279,6 +282,7 @@
 			minimizedProjectReferenceProxies = 1;
 			packageReferences = (
 				8BF100012F9A000100000001 /* XCRemoteSwiftPackageReference "swift-markdown" */,
+				8BF100062F9A000100000002 /* XCRemoteSwiftPackageReference "Splash" */,
 			);
 			preferredProjectObjectVersion = 77;
 			productRefGroup = 8B4B28D22F6704280045FA19 /* Products */;
@@ -710,6 +714,14 @@
 				minimumVersion = 0.7.3;
 			};
 		};
+		8BF100062F9A000100000002 /* XCRemoteSwiftPackageReference "Splash" */ = {
+			isa = XCRemoteSwiftPackageReference;
+			repositoryURL = "https://github.com/JohnSundell/Splash";
+			requirement = {
+				kind = upToNextMajorVersion;
+				minimumVersion = 0.16.0;
+			};
+		};
 /* End XCRemoteSwiftPackageReference section */
 
 /* Begin XCSwiftPackageProductDependency section */
@@ -718,6 +730,11 @@
 			package = 8BF100012F9A000100000001 /* XCRemoteSwiftPackageReference "swift-markdown" */;
 			productName = Markdown;
 		};
+		8BF100042F9A000100000002 /* Splash */ = {
+			isa = XCSwiftPackageProductDependency;
+			package = 8BF100062F9A000100000002 /* XCRemoteSwiftPackageReference "Splash" */;
+			productName = Splash;
+		};
 /* End XCSwiftPackageProductDependency section */
 	};
 	rootObject = 8B4B28C92F6704280045FA19 /* Project object */;
diff --git a/Hutch.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved b/Hutch.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved
index a2a45a3..ae6b756 100644
--- a/Hutch.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved
+++ b/Hutch.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved
@@ -1,7 +1,16 @@
 {
-  "originHash" : "b809819531d430dc5b7a0fb1fb5538d0321c5d541eed52a9990f37c38dd0f98a",
+  "originHash" : "65542d8a5fbbad8dd7d07c8901c1cc48b3aba12cef8da1f062bd28d9b3a6ba50",
   "pins" : [
     {
+      "identity" : "splash",
+      "kind" : "remoteSourceControl",
+      "location" : "https://github.com/JohnSundell/Splash",
+      "state" : {
+        "revision" : "7f4df436eb78fe64fe2c32c58006e9949fa28ad8",
+        "version" : "0.16.0"
+      }
+    },
+    {
       "identity" : "swift-cmark",
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/swiftlang/swift-cmark.git",