Implement per-distro installation flow

crates/aim-core/tests/install_failures.rs

@@ -0,0 +1,36 @@
+use aim_core::integration::install::{DesktopIntegrationRequest, InstallRequest, execute_install};
+use aim_core::platform::DesktopHelpers;
+use std::fs;
+use tempfile::tempdir;
+
+#[test]
+fn integration_failure_removes_new_payload_and_generated_files() {
+    let root = tempdir().unwrap();
+    let staging_root = root.path().join("staging");
+    let payload_root = root.path().join("payloads");
+    let blocking_path = root.path().join("not-a-directory");
+
+    fs::create_dir(&staging_root).unwrap();
+    fs::create_dir(&payload_root).unwrap();
+    fs::write(&blocking_path, "blocker").unwrap();
+
+    let final_payload_path = payload_root.join("bat.AppImage");
+    let desktop_entry_path = blocking_path.join("aim-bat.desktop");
+    let error = execute_install(&InstallRequest {
+        staging_root: &staging_root,
+        final_payload_path: &final_payload_path,
+        artifact_bytes: b"\x7fELFAppImage",
+        desktop: Some(DesktopIntegrationRequest {
+            desktop_entry_path: &desktop_entry_path,
+            desktop_entry_contents: "[Desktop Entry]\nName=bat\nExec=bat.AppImage\nType=Application\n",
+            icon_path: None,
+            icon_bytes: None,
+        }),
+        helpers: DesktopHelpers::default(),
+    })
+    .unwrap_err();
+
+    assert!(error.to_string().contains("desktop integration failed"));
+    assert!(!final_payload_path.exists());
+    assert!(!desktop_entry_path.exists());
+}