Add course directory manifest and upload notes

.gitattributes

@@ -1,15 +1,3 @@
-
-# Upload-only course archive
-* filter=lfs diff=lfs merge=lfs -text
-.gitattributes -filter -diff -merge text
-README.md -filter -diff -merge text
-_course_archive/Computer-Graphics-64/directory-structure.json -filter -diff -merge text
-_course_archive/Computer-Graphics-64/README.md -filter -diff -merge text
-
-# BEGIN course-upload-20261025-15
-"/补充资料-杂项-20261025/**" filter=lfs diff=lfs merge=lfs -text
-"/_course_archive/Computer-Graphics-15-20261025/**" filter=lfs diff=lfs merge=lfs -text
-/.gitattributes -filter -diff -merge text
-"/_course_archive/Computer-Graphics-15-20261025/directory-structure.json" -filter -diff -merge text
-"/_course_archive/Computer-Graphics-15-20261025/README.md" -filter -diff -merge text
-# END course-upload-20261025-15
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+size 766

_course_archive/Computer-Graphics-15-20261025/README.md

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:3865e3715b0c3efb684edb274a9f48cd55cfc53c7f5f603ce1c327decee9d631
+size 437

_course_archive/Computer-Graphics-15-20261025/directory-structure.json

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:786f66e9b05638fa2b5df9db995a545d34bcb0f4ad36b238e1895bbf929d6b88
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