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/ui/httplog_state_test.go

@@ -180,13 +180,13 @@ func TestHTTPLogState_GetFilterModeLabel(t *testing.T) {
 	state := newHTTPLogState("fwd", "alias")
 
 	tests := []struct {
-		mode     HTTPLogFilterMode
 		expected string
+		mode     HTTPLogFilterMode
 	}{
-		{HTTPLogFilterNone, "All"},
-		{HTTPLogFilterText, "Text"},
-		{HTTPLogFilterNon200, "Non-2xx"},
-		{HTTPLogFilterErrors, "Errors (4xx/5xx)"},
+		{mode: HTTPLogFilterNone, expected: "All"},
+		{mode: HTTPLogFilterText, expected: "Text"},
+		{mode: HTTPLogFilterNon200, expected: "Non-2xx"},
+		{mode: HTTPLogFilterErrors, expected: "Errors (4xx/5xx)"},
 	}
 
 	for _, tt := range tests {