chore: remove Git LFS, store binary files directly in Git

All PNG/TTF/OTF files are small (<400 KB each, ~9 MB total) and don't
benefit from LFS. Removes LFS tracking to eliminate growing storage
costs on GitHub. Also removes lfs: true from all CI workflows.

Author: RoboNET

.gitattributes

@@ -1,6 +1,4 @@
-*.png filter=lfs diff=lfs merge=lfs -text
-*.ttf filter=lfs diff=lfs merge=lfs -text
-*.otf filter=lfs diff=lfs merge=lfs -text
-*.png !text !filter !merge !diff
-*.ttf !text !filter !merge !diff
-*.otf !text !filter !merge !diff
+# Binary files - mark as binary for correct diff/merge
+*.png binary
+*.ttf binary
+*.otf binary

.github/workflows/ci.yml

@@ -19,7 +19,6 @@ jobs:
     steps:
       - uses: actions/checkout@v4
         with:
-          lfs: true
 
       - name: Setup .NET
         uses: actions/setup-dotnet@v4

.github/workflows/playground.yml

@@ -32,7 +32,6 @@ jobs:
     steps:
       - uses: actions/checkout@v4
         with:
-          lfs: true
 
       - name: Setup .NET
         uses: actions/setup-dotnet@v4

.github/workflows/release.yml

@@ -20,7 +20,6 @@ jobs:
       - uses: actions/checkout@v4
         with:
           fetch-depth: 0
-          lfs: true
 
       - name: Setup .NET
         uses: actions/setup-dotnet@v4
@@ -37,7 +36,6 @@ jobs:
       - uses: actions/checkout@v4
         with:
           fetch-depth: 0
-          lfs: true
 
       - name: Setup .NET
         uses: actions/setup-dotnet@v4
@@ -131,7 +129,6 @@ jobs:
       - uses: actions/checkout@v4
         with:
           fetch-depth: 0
-          lfs: true
 
       - name: Setup .NET
         uses: actions/setup-dotnet@v4