Make TTY output a forceable thing (#4318)

In this change, we introduce `AZD_FORCE_TTY` as a mechanism to force TTY output behavior. We removed an environment variable `AZD_TERM_SKIP_CI_DETECT` since `AZD_FORCE_TTY` is the higher-level override.

Helps with #4311

cli/azd/pkg/input/console.go

@@ -141,8 +141,15 @@ type AskerConsole struct {
 	// the writer the console was constructed with, and what we reset to when SetWriter(nil) is called.
 	defaultWriter io.Writer
 	// the writer which output is written to.
-	writer     io.Writer
-	formatter  output.Formatter
+	writer    io.Writer
+	formatter output.Formatter
+
+	// isTerminal controls whether terminal-style input/output will be used.
+	//
+	// When isTerminal is false, the following notable behaviors apply:
+	//   - Spinner progress will be written as standard newline messages.
+	//   - Prompting assumes a non-terminal environment, where output written and input received are machine-friendly text,
+	//     stripped of formatting characters.
 	isTerminal bool
 	noPrompt   bool
 	// when non nil, use this client instead of prompting ourselves on the console.
@@ -1056,24 +1063,15 @@ func NewConsole(
 // IsTerminal returns true if the given file descriptors are attached to a terminal,
 // taking into account of environment variables that force TTY behavior.
 func IsTerminal(stdoutFd uintptr, stdinFd uintptr) bool {
-	// User override to force non-TTY behavior
-	if ok, _ := strconv.ParseBool(os.Getenv("AZD_DEBUG_FORCE_NO_TTY")); ok {
-		return false
+	// User override to force TTY behavior
+	if forceTty, err := strconv.ParseBool(os.Getenv("AZD_FORCE_TTY")); err == nil {
+		return forceTty
 	}
 
 	// By default, detect if we are running on CI and force no TTY mode if we are.
-	// Allow for an override if this is not desired.
-	shouldDetectCI := true
-	if strVal, has := os.LookupEnv("AZD_TERM_SKIP_CI_DETECT"); has {
-		skip, err := strconv.ParseBool(strVal)
-		if err != nil {
-			log.Println("AZD_TERM_SKIP_CI_DETECT is not a valid boolean value")
-		} else if skip {
-			shouldDetectCI = false
-		}
-	}
-
-	if shouldDetectCI && resource.IsRunningOnCI() {
+	// If this is affecting you locally while debugging on a CI machine,
+	// use the override AZD_FORCE_TTY=true.
+	if resource.IsRunningOnCI() {
 		return false
 	}