refactor: move V1 code into v1/ subdirectory

- git mv cmd/ internal/ pkg/ test/ go.mod go.sum Makefile build.sh docs/ v1/
- Create v1/README.md with V1 documentation
- Update root README for V1 + V2 structure
- V1 still builds (cd v1 && go build ./cmd/hostkeeper) and 105 tests pass
- Root is now clean for V2 development

v1/pkg/tui/messages.go

@@ -0,0 +1,183 @@
+package tui
+
+import (
+	"context"
+
+	tea "github.com/charmbracelet/bubbletea"
+
+	"git.tukangketik.id/swanadiva/hostkeeper/internal/models"
+	"git.tukangketik.id/swanadiva/hostkeeper/pkg/storage"
+)
+
+// quitMsg signals the TUI to exit
+type quitMsg struct{}
+
+// sshConnectToMsg signals the TUI to connect to a host via native SSH
+type sshConnectToMsg struct {
+	host *models.Host
+}
+
+// sshExitMsg signals that a native SSH session has ended
+type sshExitMsg struct {
+	err error
+}
+
+// openHostFormMsg signals the TUI to open a host form tab
+type openHostFormMsg struct {
+	editing *models.Host // nil for add mode
+}
+
+// closeFormMsg signals the TUI to close the active form tab
+type closeFormMsg struct{}
+
+// saveHostMsg is produced when the form needs to save a host
+type saveHostMsg struct {
+	host    *models.Host
+	dataDir string
+}
+
+// saveHostResultMsg is produced after a save attempt
+type saveHostResultMsg struct {
+	host *models.Host
+	err  error
+}
+
+// openSFTPMsg signals the TUI to open an SFTP browser tab
+type openSFTPMsg struct {
+	host *models.Host
+}
+
+// loadedHostsMsg is produced after reloading hosts from storage
+type loadedHostsMsg struct {
+	hosts []*models.Host
+}
+
+// Key management messages
+type openKeyListMsg struct{}
+
+type openKeyFormMsg struct {
+	editing *models.KeyPair
+}
+
+type saveKeyMsg struct {
+	key     *models.KeyPair
+	dataDir string
+}
+
+type saveKeyResultMsg struct {
+	key *models.KeyPair
+	err error
+}
+
+type deleteKeyMsg struct {
+	id      string
+	dataDir string
+}
+
+type deleteKeyResultMsg struct {
+	err error
+}
+
+// Snippet management messages
+type openSnippetListMsg struct{}
+
+type openSnippetFormMsg struct {
+	editing *models.Snippet
+}
+
+type saveSnippetMsg struct {
+	snippet *models.Snippet
+	dataDir string
+}
+
+type saveSnippetResultMsg struct {
+	snippet *models.Snippet
+	err     error
+}
+
+type deleteSnippetMsg struct {
+	id      string
+	dataDir string
+}
+
+type deleteSnippetResultMsg struct {
+	err error
+}
+
+// saveKeyCmd creates a command that saves a key pair to storage
+func saveKeyCmd(key *models.KeyPair, dataDir string) tea.Cmd {
+	return func() tea.Msg {
+		store, err := storage.NewJSONStorage(dataDir)
+		if err != nil {
+			return saveKeyResultMsg{err: err}
+		}
+		ctx := context.Background()
+		if err := store.SaveKeyPair(ctx, key); err != nil {
+			return saveKeyResultMsg{err: err}
+		}
+		return saveKeyResultMsg{key: key}
+	}
+}
+
+// deleteKeyCmd creates a command that deletes a key pair
+func deleteKeyCmd(id, dataDir string) tea.Cmd {
+	return func() tea.Msg {
+		store, err := storage.NewJSONStorage(dataDir)
+		if err != nil {
+			return deleteKeyResultMsg{err: err}
+		}
+		ctx := context.Background()
+		if err := store.DeleteKeyPair(ctx, id); err != nil {
+			return deleteKeyResultMsg{err: err}
+		}
+		return deleteKeyResultMsg{}
+	}
+}
+
+// saveSnippetCmd creates a command that saves a snippet to storage
+func saveSnippetCmd(snippet *models.Snippet, dataDir string) tea.Cmd {
+	return func() tea.Msg {
+		store, err := storage.NewJSONStorage(dataDir)
+		if err != nil {
+			return saveSnippetResultMsg{err: err}
+		}
+		ctx := context.Background()
+		if err := store.SaveSnippet(ctx, snippet); err != nil {
+			return saveSnippetResultMsg{err: err}
+		}
+		return saveSnippetResultMsg{snippet: snippet}
+	}
+}
+
+// deleteSnippetCmd creates a command that deletes a snippet
+func deleteSnippetCmd(id, dataDir string) tea.Cmd {
+	return func() tea.Msg {
+		store, err := storage.NewJSONStorage(dataDir)
+		if err != nil {
+			return deleteSnippetResultMsg{err: err}
+		}
+		ctx := context.Background()
+		if err := store.DeleteSnippet(ctx, id); err != nil {
+			return deleteSnippetResultMsg{err: err}
+		}
+		return deleteSnippetResultMsg{}
+	}
+}
+
+// saveHostCmd creates a command that saves a host to storage
+func saveHostCmd(host *models.Host, dataDir string) tea.Cmd {
+	return func() tea.Msg {
+		store, err := storage.NewJSONStorage(dataDir)
+		if err != nil {
+			return saveHostResultMsg{err: err}
+		}
+		ctx := context.Background()
+		if err := store.SaveHost(ctx, host); err != nil {
+			return saveHostResultMsg{err: err}
+		}
+		return saveHostResultMsg{host: host}
+	}
+}
+
+// openEncryptPromptMsg shows the encryption setup prompt
+type openEncryptPromptMsg struct{}