Rename app from Snipping Tool to SnipMC

Changes bundle ID, URL scheme, display name, project name,
and all user-facing references.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

SnipMC.xcodeproj/project.xcworkspace/contents.xcworkspacedata

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Workspace
+   version = "1.0">
+   <FileRef
+      location = "self:">
+   </FileRef>
+</Workspace>