feat: nushell completions

Signed-off-by: jolheiser <john.olheiser@gmail.com>

contrib/kv.nu

@@ -0,0 +1,21 @@
+def keys [] {
+  ^kv list | lines | each { |line| $line | str trim }
+}
+
+export extern "kv get" [
+  key: string@keys # Key
+]
+
+export extern "kv set" [
+  key: string      # Key
+  value: string    # Value
+  ...value: string # Value cont.
+]
+
+export extern "kv del" [
+  key: string@keys #Key
+]
+
+export extern "kv list" [
+  prefix?: string # Key prefix filter
+]