refactor: Create SigningDriver and CiDriver (#197)

This also includes a new `login` command. The signing and CI logic is now using the Driver trait system along with a new experimental sigstore signing driver. New static macros have also been created to make implementation management easier for `Command` usage and `Driver` trait implementation calls.

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Co-authored-by: xyny <60004820+xynydev@users.noreply.github.com>

process/process.rs

@@ -0,0 +1,57 @@
+//! This module is responsible for managing processes spawned
+//! by this tool. It contains drivers for running, building, inspecting, and signing
+//! images that interface with tools like docker or podman.
+
+#[cfg(feature = "sigstore")]
+use once_cell::sync::Lazy;
+#[cfg(feature = "sigstore")]
+use tokio::runtime::Runtime;
+
+pub mod drivers;
+pub mod logging;
+pub mod signal_handler;
+
+#[cfg(feature = "sigstore")]
+pub(crate) static RT: Lazy<Runtime> = Lazy::new(|| {
+    tokio::runtime::Builder::new_multi_thread()
+        .enable_all()
+        .build()
+        .unwrap()
+});
+
+#[cfg(test)]
+pub(crate) mod test {
+    use std::sync::Mutex;
+
+    use blue_build_recipe::{Module, ModuleExt, Recipe};
+    use indexmap::IndexMap;
+    use once_cell::sync::Lazy;
+
+    pub const BB_UNIT_TEST_MOCK_GET_OS_VERSION: &str = "BB_UNIT_TEST_MOCK_GET_OS_VERSION";
+
+    /// This mutex is used for tests that require the reading of
+    /// environment variables. Env vars are an inheritly unsafe
+    /// as they can be changed and affect other threads functionality.
+    ///
+    /// For tests that require setting env vars, they need to lock this
+    /// mutex before making changes to the env. Any changes made to the env
+    /// MUST be undone in the same test before dropping the lock. Failure to
+    /// do so will cause unpredictable behavior with other tests.
+    pub static ENV_LOCK: Lazy<Mutex<()>> = Lazy::new(|| Mutex::new(()));
+
+    pub fn create_test_recipe() -> Recipe<'static> {
+        Recipe::builder()
+            .name("test")
+            .description("This is a test")
+            .base_image("base-image")
+            .image_version("40")
+            .modules_ext(
+                ModuleExt::builder()
+                    .modules(vec![Module::builder().build()])
+                    .build(),
+            )
+            .stages_ext(None)
+            .extra(IndexMap::new())
+            .build()
+    }
+}