init: MVP remote desktop (agent/viewer/common) with H.264 pipeline

.gitignore

@@ -0,0 +1,26 @@
+# ===== Rust / Cargo =====
+/target
+**/*.rs.bk
+
+# ===== 构建产物 =====
+*.exe
+*.dll
+*.pdb
+*.lib
+*.a
+
+# ===== 运行时生成 =====
+*.log
+identity.pem
+*.pem
+*.der
+
+# ===== IDE / 编辑器 =====
+.idea/
+.vscode/
+*.swp
+*~
+
+# ===== 系统文件 =====
+Thumbs.db
+.DS_Store