deps: update vendor dependencies for S3-compatible storage

Updates AWS SDK and removes Blazer B2 dependency in favor of unified
S3-compatible approach. Includes configuration examples and documentation.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

vendor/github.com/aws/aws-sdk-go/internal/sdkrand/read.go

@@ -0,0 +1,12 @@
+//go:build go1.6
+// +build go1.6
+
+package sdkrand
+
+import "math/rand"
+
+// Read provides the stub for math.Rand.Read method support for go version's
+// 1.6 and greater.
+func Read(r *rand.Rand, p []byte) (int, error) {
+	return r.Read(p)
+}