Add Phase 5 enhancements: security, i18n, analysis, backup, notifications

- Database v8 migration: tags, pinned, avg_startup_ms columns
- Security scanning with CVE matching and batch scan
- Bundled library extraction and vulnerability reports
- Desktop notification system for security alerts
- Backup/restore system for AppImage configurations
- i18n framework with gettext support
- Runtime analysis and Wayland compatibility detection
- AppStream metadata and Flatpak-style build support
- File watcher module for live directory monitoring
- Preferences panel with GSettings integration
- CLI interface for headless operation
- Detail view: tabbed layout with ViewSwitcher in title bar,
  health score, sandbox controls, changelog links
- Library view: sort dropdown, context menu enhancements
- Dashboard: system status, disk usage, launch history
- Security report page with scan and export
- Packaging: meson build, PKGBUILD, metainfo

src/core/appstream.rs

@@ -0,0 +1,209 @@
+use std::fs;
+use std::path::PathBuf;
+
+use super::database::Database;
+
+/// Generate an AppStream catalog XML from the Driftwood database.
+/// This allows GNOME Software / KDE Discover to see locally managed AppImages.
+pub fn generate_catalog(db: &Database) -> Result<String, AppStreamError> {
+    let records = db.get_all_appimages()
+        .map_err(|e| AppStreamError::Database(e.to_string()))?;
+
+    let mut xml = String::from("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n");
+    xml.push_str("<components version=\"0.16\" origin=\"driftwood\">\n");
+
+    for record in &records {
+        let app_name = record.app_name.as_deref().unwrap_or(&record.filename);
+        let app_id = make_component_id(app_name);
+        let description = record.description.as_deref().unwrap_or("");
+
+        xml.push_str("  <component type=\"desktop-application\">\n");
+        xml.push_str(&format!("    <id>appimage.{}</id>\n", xml_escape(&app_id)));
+        xml.push_str(&format!("    <name>{}</name>\n", xml_escape(app_name)));
+
+        if !description.is_empty() {
+            xml.push_str(&format!("    <summary>{}</summary>\n", xml_escape(description)));
+        }
+
+        xml.push_str(&format!("    <pkgname>{}</pkgname>\n", xml_escape(&record.filename)));
+
+        if let Some(version) = &record.app_version {
+            xml.push_str("    <releases>\n");
+            xml.push_str(&format!(
+                "      <release version=\"{}\" />\n",
+                xml_escape(version),
+            ));
+            xml.push_str("    </releases>\n");
+        }
+
+        if let Some(categories) = &record.categories {
+            xml.push_str("    <categories>\n");
+            for cat in categories.split(';').filter(|c| !c.is_empty()) {
+                xml.push_str(&format!("      <category>{}</category>\n", xml_escape(cat.trim())));
+            }
+            xml.push_str("    </categories>\n");
+        }
+
+        // Provide hint about source
+        xml.push_str("    <metadata>\n");
+        xml.push_str("      <value key=\"managed-by\">driftwood</value>\n");
+        xml.push_str(&format!(
+            "      <value key=\"appimage-path\">{}</value>\n",
+            xml_escape(&record.path),
+        ));
+        xml.push_str("    </metadata>\n");
+
+        xml.push_str("  </component>\n");
+    }
+
+    xml.push_str("</components>\n");
+    Ok(xml)
+}
+
+/// Install the AppStream catalog to the local swcatalog directory.
+/// GNOME Software reads from `~/.local/share/swcatalog/xml/`.
+pub fn install_catalog(db: &Database) -> Result<PathBuf, AppStreamError> {
+    let catalog_xml = generate_catalog(db)?;
+
+    let catalog_dir = dirs::data_dir()
+        .unwrap_or_else(|| PathBuf::from("~/.local/share"))
+        .join("swcatalog")
+        .join("xml");
+
+    fs::create_dir_all(&catalog_dir)
+        .map_err(|e| AppStreamError::Io(e.to_string()))?;
+
+    let catalog_path = catalog_dir.join("driftwood.xml");
+    fs::write(&catalog_path, &catalog_xml)
+        .map_err(|e| AppStreamError::Io(e.to_string()))?;
+
+    Ok(catalog_path)
+}
+
+/// Remove the AppStream catalog from the local swcatalog directory.
+pub fn uninstall_catalog() -> Result<(), AppStreamError> {
+    let catalog_path = dirs::data_dir()
+        .unwrap_or_else(|| PathBuf::from("~/.local/share"))
+        .join("swcatalog")
+        .join("xml")
+        .join("driftwood.xml");
+
+    if catalog_path.exists() {
+        fs::remove_file(&catalog_path)
+            .map_err(|e| AppStreamError::Io(e.to_string()))?;
+    }
+
+    Ok(())
+}
+
+/// Check if the AppStream catalog is currently installed.
+pub fn is_catalog_installed() -> bool {
+    let catalog_path = dirs::data_dir()
+        .unwrap_or_else(|| PathBuf::from("~/.local/share"))
+        .join("swcatalog")
+        .join("xml")
+        .join("driftwood.xml");
+
+    catalog_path.exists()
+}
+
+// --- Utility functions ---
+
+fn make_component_id(name: &str) -> String {
+    name.chars()
+        .map(|c| if c.is_alphanumeric() || c == '-' || c == '.' { c.to_ascii_lowercase() } else { '_' })
+        .collect::<String>()
+        .trim_matches('_')
+        .to_string()
+}
+
+fn xml_escape(s: &str) -> String {
+    s.replace('&', "&amp;")
+        .replace('<', "&lt;")
+        .replace('>', "&gt;")
+        .replace('"', "&quot;")
+        .replace('\'', "&apos;")
+}
+
+// --- Error types ---
+
+#[derive(Debug)]
+pub enum AppStreamError {
+    Database(String),
+    Io(String),
+}
+
+impl std::fmt::Display for AppStreamError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Self::Database(e) => write!(f, "Database error: {}", e),
+            Self::Io(e) => write!(f, "I/O error: {}", e),
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_make_component_id() {
+        assert_eq!(make_component_id("Firefox"), "firefox");
+        assert_eq!(make_component_id("My App 2.0"), "my_app_2.0");
+        assert_eq!(make_component_id("GIMP"), "gimp");
+    }
+
+    #[test]
+    fn test_xml_escape() {
+        assert_eq!(xml_escape("hello & world"), "hello &amp; world");
+        assert_eq!(xml_escape("<tag>"), "&lt;tag&gt;");
+        assert_eq!(xml_escape("it's \"quoted\""), "it&apos;s &quot;quoted&quot;");
+    }
+
+    #[test]
+    fn test_generate_catalog_empty() {
+        let db = crate::core::database::Database::open_in_memory().unwrap();
+        let xml = generate_catalog(&db).unwrap();
+        assert!(xml.contains("<components"));
+        assert!(xml.contains("</components>"));
+        // No individual component entries in an empty DB
+        assert!(!xml.contains("<component "));
+    }
+
+    #[test]
+    fn test_generate_catalog_with_app() {
+        let db = crate::core::database::Database::open_in_memory().unwrap();
+        db.upsert_appimage(
+            "/tmp/test.AppImage",
+            "test.AppImage",
+            Some(2),
+            1024,
+            true,
+            None,
+        ).unwrap();
+        db.update_metadata(
+            1,
+            Some("TestApp"),
+            Some("1.0"),
+            None,
+            None,
+            Some("Utility;"),
+            None,
+            None,
+            None,
+        ).ok();
+
+        let xml = generate_catalog(&db).unwrap();
+        assert!(xml.contains("appimage.testapp"));
+        assert!(xml.contains("<pkgname>test.AppImage</pkgname>"));
+        assert!(xml.contains("managed-by"));
+    }
+
+    #[test]
+    fn test_appstream_error_display() {
+        let err = AppStreamError::Database("db error".to_string());
+        assert!(format!("{}", err).contains("db error"));
+        let err = AppStreamError::Io("write failed".to_string());
+        assert!(format!("{}", err).contains("write failed"));
+    }
+}