feat(cli): orca node key-reset <node> — local known_hosts reset (T02.8, REQ-059)

---ci---
project: orca
phase: 2
milestone: v0.8
status: execute
---/ci---

internal/cli/node.go

@@ -346,6 +346,64 @@ func renderNodeTable(nodes []*model.Node) string {
 	return out
 }
 
+var nodeKeyResetCmd = &cobra.Command{
+	Use:   "key-reset <node>",
+	Short: "Reset the SSH known_hosts entry for a node",
+	Long: `Remove the pinned SSH host key for <node> from the local known_hosts
+file. The next connect re-pins the key via TOFU or --host-key-fingerprint.
+
+LOCAL ONLY (D-046): does not touch the remote host's authorized_keys.
+
+<node> is the node name (for proxmox nodes, this is the host address).`,
+	Args: cobra.ExactArgs(1),
+	RunE: func(cmd *cobra.Command, args []string) error {
+		nodeArg := args[0]
+
+		registry, closer, err := nodeRegistry()
+		if err != nil {
+			return err
+		}
+		defer closer()
+
+		ctx, cancel := context.WithTimeout(cmd.Context(), 5*time.Second)
+		defer cancel()
+
+		nodes, err := registry.List(ctx)
+		if err != nil {
+			return fmt.Errorf("list nodes: %w", err)
+		}
+		var node *model.Node
+		for _, n := range nodes {
+			if n.Name == nodeArg || n.ID == nodeArg {
+				node = n
+				break
+			}
+		}
+		if node == nil {
+			return fmt.Errorf("node %q not found in the registry", nodeArg)
+		}
+		host := node.Name
+
+		if err := proxmox.ResetHostKey(host); err != nil {
+			return fmt.Errorf("reset host key: %w", err)
+		}
+
+		// Audit-log the reset (REQ-059): actor=cli, action=node.key_reset.
+		db, dbCloser, dbErr := openDB()
+		if dbErr == nil {
+			defer dbCloser()
+			audit := engine.NewAudit(store.NewAuditRepo(db), newLogger())
+			audit.Record(ctx, "cli", "node.key_reset", node.ID, "success", nil, map[string]any{
+				"node": node.Name,
+				"host": host,
+			})
+		}
+
+		fmt.Fprintf(cmd.OutOrStdout(), "✓ Host key reset for %s (next connect will re-pin via TOFU or --host-key-fingerprint)\n", node.Name)
+		return nil
+	},
+}
+
 func init() {
 	nodeJoinCmd.Flags().StringVar(&joinName, "name", "", "node name (required for --type localhost)")
 	nodeJoinCmd.Flags().StringVar(&joinAddr, "addr", "", "node address (default localhost:8443)")
@@ -364,5 +422,6 @@ func init() {
 	nodeCmd.AddCommand(nodeJoinCmd)
 	nodeCmd.AddCommand(nodeLeaveCmd)
 	nodeCmd.AddCommand(nodeListCmd)
+	nodeCmd.AddCommand(nodeKeyResetCmd)
 	rootCmd.AddCommand(nodeCmd)
 }