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/version/checker.go

@@ -1,3 +1,15 @@
+// Package version provides version checking against GitHub releases.
+// It queries the GitHub API to check for newer versions of kportal
+// and provides update notifications.
+//
+// Basic usage:
+//
+//	info, err := version.CheckForUpdate(ctx, "owner", "repo", "v1.0.0")
+//	if err != nil {
+//	    log.Printf("Version check failed: %v", err)
+//	} else if info.UpdateAvailable {
+//	    fmt.Printf("Update available: %s -> %s\n", info.CurrentVersion, info.LatestVersion)
+//	}
 package version
 
 import (
@@ -33,10 +45,10 @@ type UpdateInfo struct {
 
 // Checker checks for new versions on GitHub
 type Checker struct {
+	client  *http.Client
 	owner   string
 	repo    string
 	current string
-	client  *http.Client
 }
 
 // NewChecker creates a new version checker