feat: add config edit command to open config in editor

New subcommand 'kctl-tui config edit' opens ~/.kctl-tui/config.yaml
in the user's editor. Respects VISUAL/EDITOR env vars, falls back to
notepad on Windows and vim on Linux/macOS. Creates the config directory
and a starter file if they don't exist yet.

README.md

@@ -119,7 +119,8 @@ matching asset from the [Releases page](https://github.com/skoelle/kctl-tui/rele
 ## ⚙️ Configuration
 
 Copy [config.example.yaml](config.example.yaml) to `~/.kctl-tui/config.yaml`
-and adjust it to your own setup:
+and adjust it to your own setup — or use `kctl-tui config edit` to open the
+file directly in your editor (creates the file and directory if needed):
 
 ```yaml
 contexts:
@@ -136,6 +137,7 @@ aws_account_id: "123456789012"
 
 secret_name_template: "tf-{namespace}-{env}-secrets"
 k8s_secret_name_template: "{namespace}-common-secrets"
+external_secret_name_template: "{namespace}"
 context_template: "arn:aws:eks:{region}:{account_id}:cluster/tf-{env}-{context}-1"
 
 team_label_key: "example.org/team"
@@ -159,6 +161,12 @@ aws_sso_login_command: "aws sso login"
   chosen namespace. Kept separate from `secret_name_template` because the
   two sides commonly follow different naming conventions. Placeholders:
   `{namespace}`.
+- 🎯 `external_secret_name_template`: builds the ExternalSecret CRD object
+  name to annotate when a force-sync is requested. This is often different
+  from the Kubernetes secret name because the ExternalSecret CRD and the
+  resulting Secret are separate objects (e.g. ExternalSecret `"job-apply"`
+  produces Secret `"job-apply-common-secrets"`). Falls back to
+  `k8s_secret_name_template` if omitted. Placeholders: `{namespace}`.
 - 🔗 `context_template`: builds the actual kubectl context name/ARN from
   region, account ID, environment, and context. Placeholders: `{region}`,
   `{account_id}`, `{env}`, `{context}`. Adjust the literal parts (`tf-`,
@@ -205,6 +213,7 @@ kctl-tui --version          # print version
 kctl-tui --verbose          # enable debug logging to stderr
 kctl-tui update             # update to the latest release
 kctl-tui doctor             # check if all tools, config and connections are OK
+kctl-tui config edit        # open ~/.kctl-tui/config.yaml in your editor
 kctl-tui config check       # validate ~/.kctl-tui/config.yaml
 kctl-tui panel --context=... --ns=... --team=...   # internal (called by tmux)
 ```

cmd/kctl-tui/main.go

@@ -6,6 +6,9 @@ package main
 import (
 	"fmt"
 	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
 
 	tea "github.com/charmbracelet/bubbletea"
 
@@ -113,6 +116,7 @@ Usage:
   kctl-tui [flags]             start the TUI (full navigation mode)
   kctl-tui doctor              check tools, config and connections
   kctl-tui update              update to the latest release
+  kctl-tui config edit         open ~/.kctl-tui/config.yaml in editor
   kctl-tui config check        validate ~/.kctl-tui/config.yaml
   kctl-tui panel [options]     control pane (called internally by tmux)
 
@@ -126,14 +130,56 @@ Examples:
   kctl-tui doctor                   # verify everything is installed
   kctl-tui update                   # update to the latest version
   kctl-tui --verbose 2>debug.log    # log commands to a file
+  kctl-tui config edit              # open config in editor
   kctl-tui config check             # validate config
 `)
 }
 
 func runConfig(args []string) error {
-	if len(args) == 0 || args[0] != "check" {
-		return fmt.Errorf("usage: kctl-tui config check")
+	if len(args) > 0 && args[0] == "check" {
+		return runConfigCheck()
 	}
+	if len(args) == 0 || args[0] == "edit" {
+		return runConfigEdit()
+	}
+	return fmt.Errorf("usage: kctl-tui config [check|edit]")
+}
+
+func runConfigEdit() error {
+	cfgPath, err := config.DefaultPath()
+	if err != nil {
+		return fmt.Errorf("cannot determine config path: %w", err)
+	}
+	dir := filepath.Dir(cfgPath)
+	if err := os.MkdirAll(dir, 0o700); err != nil {
+		return fmt.Errorf("cannot create config directory %s: %w", dir, err)
+	}
+	if _, err := os.Stat(cfgPath); os.IsNotExist(err) {
+		if err := os.WriteFile(cfgPath, []byte("# kctl-tui configuration\n# See https://github.com/skoelle/kctl-tui for examples.\n"), 0o600); err != nil {
+			return fmt.Errorf("cannot create config file %s: %w", cfgPath, err)
+		}
+		fmt.Printf("Created new config file: %s\n", cfgPath)
+	}
+	editor := os.Getenv("VISUAL")
+	if editor == "" {
+		editor = os.Getenv("EDITOR")
+	}
+	if editor == "" {
+		switch runtime.GOOS {
+		case "windows":
+			editor = "notepad"
+		default:
+			editor = "vim"
+		}
+	}
+	cmd := exec.Command(editor, cfgPath)
+	cmd.Stdin = os.Stdin
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	return cmd.Run()
+}
+
+func runConfigCheck() error {
 	cfgPath, err := config.DefaultPath()
 	if err != nil {
 		return fmt.Errorf("cannot determine config path: %w", err)