Implement interrupt handling for long-running commands and archive extraction

- Added an `interrupts` module to manage Ctrl-C signals and propagate them to child processes.
- Refactored archive extraction functions to check for interrupts and handle them gracefully.
- Introduced `copy_interruptibly` function to allow for interruptible copying of data.
- Updated various source files to utilize the new interrupt handling functions, ensuring that commands and archive extractions can be interrupted by the user.
- Added tests to verify the interrupt functionality during copying and tar extraction.
- Introduced a new Meson option for generating HTML CLI documentation.
- Enhanced the `PackageSpec` struct to support additional Rust LTO flags.

src/package/interactive.rs

@@ -942,6 +942,19 @@ pub fn spec_to_minimal_toml(spec: &PackageSpec) -> anyhow::Result<String> {
             ),
         );
     }
+    if !spec.build.flags.rustltoflags.is_empty() {
+        flags_tbl.insert(
+            "rustltoflags".into(),
+            Value::Array(
+                spec.build
+                    .flags
+                    .rustltoflags
+                    .iter()
+                    .map(|s| Value::String(s.clone()))
+                    .collect(),
+            ),
+        );
+    }
     if !spec.build.flags.keep.is_empty() {
         flags_tbl.insert(
             "keep".into(),