Refactor to consolidate APIs into contract package and introduce NFT interface for better modularity and maintainability.

contract/nft.go

@@ -0,0 +1,31 @@
+package contract
+
+import "git.kor-elf.net/kor-elf-shield/go-nftables-client/contract/nft"
+
+// NFT A client for working with nftables
+type NFT interface {
+	// Command returns the command used to execute nft.
+	// You can execute your raw request.
+	Command() Command
+
+	// Clear clears all rules.
+	//
+	// This command is equivalent to:
+	//    nft flush ruleset
+	Clear() error
+
+	// Version returns the version of nftables.
+	//
+	// This command is equivalent to:
+	//    nft -V
+	Version() (nft.Version, error)
+
+	// Table returns an API for working with tables.
+	Table() nft.Table
+
+	// Chain returns an API for working with chains.
+	Chain() nft.Chain
+
+	// Rule returns an API for working with rules.
+	Rule() nft.Rule
+}