feat(cli): enhance install and removal UX with progress visibility and theming

- Introduced visible progress stages during installation, including source resolution and artifact selection.
- Improved separation between live transcript output and final summaries, ensuring clarity.
- Removed redundant recap text from installation summaries.
- Centralized terminal styling using a configurable theme system, allowing for warm defaults and user overrides.
- Added support for hex colors and named colors in the configuration.
- Updated tests to verify new behaviors and configurations.

crates/aim-cli/src/main.rs

@@ -1,10 +1,24 @@
 fn main() {
+    let loaded_config = aim_cli::cli::config::AppConfig::load();
+    aim_cli::ui::theme::set_active_theme(aim_cli::ui::theme::resolve_theme(
+        &loaded_config.config.theme,
+    ));
+    for warning in loaded_config.warnings {
+        eprintln!(
+            "{}",
+            aim_cli::ui::theme::warning_text(&format!("Config warning: {warning}"))
+        );
+    }
+
     let cli = aim_cli::parse();
     let mut reporter = aim_cli::ui::progress::TerminalProgressReporter::stderr();
     match aim_cli::dispatch_with_reporter(cli, &mut reporter) {
         Ok(result) => {
             let output = aim_cli::render(&result);
             if !output.is_empty() {
+                if reporter.emitted_output() {
+                    println!();
+                }
                 println!("{output}");
             }
         }