feat: CLI UX overhaul with colored output, timing, shorthands, and fuzzy suggestions

Add polished CLI output across all commands: colored help text, green/red
pass/fail indicators (✓/✗), elapsed timing on compile/check/test/fmt,
command shorthands (c/t/f/s/k), fuzzy "did you mean?" on typos, and
smart port-in-use suggestions for serve. Respects NO_COLOR/TERM=dumb.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/diagnostics.rs

@@ -224,10 +224,31 @@ pub mod colors {
     pub const BOLD: &str = "\x1b[1m";
     pub const DIM: &str = "\x1b[2m";
     pub const RED: &str = "\x1b[31m";
+    pub const GREEN: &str = "\x1b[32m";
     pub const YELLOW: &str = "\x1b[33m";
     pub const BLUE: &str = "\x1b[34m";
+    pub const MAGENTA: &str = "\x1b[35m";
     pub const CYAN: &str = "\x1b[36m";
     pub const WHITE: &str = "\x1b[37m";
+    pub const GRAY: &str = "\x1b[90m";
+}
+
+/// Apply color to text, respecting NO_COLOR / TERM=dumb
+pub fn c(color: &str, text: &str) -> String {
+    if supports_color() {
+        format!("{}{}{}", color, text, colors::RESET)
+    } else {
+        text.to_string()
+    }
+}
+
+/// Apply bold + color to text
+pub fn bc(color: &str, text: &str) -> String {
+    if supports_color() {
+        format!("{}{}{}{}", colors::BOLD, color, text, colors::RESET)
+    } else {
+        text.to_string()
+    }
 }
 
 /// Severity level for diagnostics