style: Extract UI constants and refactor main view rendering (#30)

- [x] Add golangci-lint configuration with gocritic ifElseChain disabled
- [x] Rename error variables to avoid shadowing (createErr, watcherErr, watchErr, etc.)
- [x] Replace `interface{}` with `any` type alias throughout codebase
- [x] Add package-level documentation comments to all internal packages
- [x] Reorder struct fields alphabetically for consistency
- [x] Extract UI constants (terminal dimensions, column widths, colors) to constants.go
- [x] Refactor BubbleTeaUI main view rendering into smaller helper functions
- [x] Simplify nested conditionals and improve code clarity
- [x] Add `isForwardDisabled()` helper method to BubbleTeaUI
- [x] Update file permissions from 0644 to 0600 in config tests
- [x] Add `#nosec` comments and error suppression where appropriate
- [x] Improve test table struct field ordering for readability
- [x] Fix resource parsing in AddForward using strings.SplitN
- [x] Add comprehensive tests for new UI helper functions and constants

internal/converter/kftray.go

@@ -1,3 +1,12 @@
+// Package converter provides configuration migration from other port-forwarding
+// tools to kportal's YAML format. Currently supports kftray JSON format.
+//
+// Basic usage:
+//
+//	err := converter.ConvertKFTrayToKPortal("kftray.json", ".kportal.yaml")
+//	if err != nil {
+//	    log.Fatal(err)
+//	}
 package converter
 
 import (
@@ -14,12 +23,12 @@ import (
 type KFTrayConfig struct {
 	Service      string `json:"service"`
 	Namespace    string `json:"namespace"`
-	LocalPort    int    `json:"local_port"`
-	RemotePort   int    `json:"remote_port"`
 	Context      string `json:"context"`
 	WorkloadType string `json:"workload_type"`
 	Protocol     string `json:"protocol"`
 	Alias        string `json:"alias"`
+	LocalPort    int    `json:"local_port"`
+	RemotePort   int    `json:"remote_port"`
 }
 
 // ConvertKFTrayToKPortal converts kftray JSON configuration to kportal YAML format
@@ -32,8 +41,8 @@ func ConvertKFTrayToKPortal(inputFile, outputFile string) error {
 	}
 
 	var kftrayConfigs []KFTrayConfig
-	if err := json.Unmarshal(data, &kftrayConfigs); err != nil {
-		return fmt.Errorf("failed to parse JSON: %w", err)
+	if unmarshalErr := json.Unmarshal(data, &kftrayConfigs); unmarshalErr != nil {
+		return fmt.Errorf("failed to parse JSON: %w", unmarshalErr)
 	}
 
 	// Convert to kportal format
@@ -169,9 +178,9 @@ type namespaceEntry struct {
 type forwardEntry struct {
 	Resource  string `yaml:"resource"`
 	Protocol  string `yaml:"protocol"`
+	Alias     string `yaml:"alias,omitempty"`
 	Port      int    `yaml:"port"`
 	LocalPort int    `yaml:"localPort"`
-	Alias     string `yaml:"alias,omitempty"`
 }
 
 // Convert internal types to config package types