build: Update binaries to v3.0.0

- Updated build_all.sh VERSION to 3.0.0
- Rebuilt all 10 cross-platform binaries
- Updated bin/README.md with v3.0.0 features
- All binaries now correctly report version 3.0.0

Platforms: Linux (x3), macOS (x2), Windows (x2), BSD (x3)

build_all.sh

@@ -15,7 +15,7 @@ echo "🔧 Using Go version: $GO_VERSION"
 
 # Configuration
 APP_NAME="dbbackup"
-VERSION="1.1.0"
+VERSION="3.0.0"
 BUILD_TIME=$(date -u '+%Y-%m-%d_%H:%M:%S_UTC')
 GIT_COMMIT=$(git rev-parse --short HEAD 2>/dev/null || echo "unknown")
 BIN_DIR="bin"