chore: rebrand from Kon/Corbie to Magnotia

Replace all instances of the legacy product names "Kon" and "Corbie" with
"Magnotia" across user-facing copy, code identifiers, package names, bundle
ids, file paths, and documentation. Preserves the unrelated "konsole" (KDE
terminal) reference and the parent CORBEL company name.

- Renames 10 Rust crates (kon-* → magnotia-*) and the tauri binary
- Updates package.json, tauri.conf.json (productName + identifier)
- Renames CSS classes (kon-rh-* → magnotia-rh-*) and animations
- Renames brand and roadmap docs
- Regenerates Cargo.lock and package-lock.json

Verified: svelte-check passes; pure-rust crates compile under new names.

crates/core/src/paths.rs

@@ -19,7 +19,7 @@ impl AppPaths {
     }
 
     pub fn database_path(&self) -> PathBuf {
-        self.app_data_dir.join("kon.db")
+        self.app_data_dir.join("magnotia.db")
     }
 
     pub fn recordings_dir(&self) -> PathBuf {
@@ -67,7 +67,7 @@ fn resolve_app_data_dir() -> PathBuf {
     #[cfg(target_os = "windows")]
     {
         let local_app_data = std::env::var("LOCALAPPDATA").unwrap_or_else(|_| ".".to_string());
-        return PathBuf::from(local_app_data).join("kon");
+        return PathBuf::from(local_app_data).join("magnotia");
     }
 
     #[cfg(target_os = "macos")]
@@ -76,28 +76,28 @@ fn resolve_app_data_dir() -> PathBuf {
         return PathBuf::from(home)
             .join("Library")
             .join("Application Support")
-            .join("Kon");
+            .join("Magnotia");
     }
 
     #[cfg(target_os = "linux")]
     {
         let home = std::env::var("HOME").unwrap_or_else(|_| "/tmp".to_string());
-        let legacy = PathBuf::from(&home).join(".kon");
+        let legacy = PathBuf::from(&home).join(".magnotia");
         if legacy.exists() {
             return legacy;
         }
         if let Ok(xdg) = std::env::var("XDG_DATA_HOME") {
             if !xdg.is_empty() {
-                return PathBuf::from(xdg).join("kon");
+                return PathBuf::from(xdg).join("magnotia");
             }
         }
-        PathBuf::from(home).join(".local").join("share").join("kon")
+        PathBuf::from(home).join(".local").join("share").join("magnotia")
     }
 
     #[cfg(not(any(target_os = "windows", target_os = "macos", target_os = "linux")))]
     {
         let home = std::env::var("HOME").unwrap_or_else(|_| "/tmp".to_string());
-        PathBuf::from(home).join(".kon")
+        PathBuf::from(home).join(".magnotia")
     }
 }
 
@@ -110,16 +110,16 @@ mod tests {
     #[test]
     fn derives_all_paths_from_one_base() {
         let paths = AppPaths {
-            app_data_dir: PathBuf::from("/tmp/kon-test"),
+            app_data_dir: PathBuf::from("/tmp/magnotia-test"),
         };
-        assert_eq!(paths.database_path(), PathBuf::from("/tmp/kon-test/kon.db"));
+        assert_eq!(paths.database_path(), PathBuf::from("/tmp/magnotia-test/magnotia.db"));
         assert_eq!(
             paths.speech_model_dir(&ModelId::new("whisper-base-en")),
-            PathBuf::from("/tmp/kon-test/models/whisper-base-en")
+            PathBuf::from("/tmp/magnotia-test/models/whisper-base-en")
         );
         assert_eq!(
             paths.llm_models_dir(),
-            PathBuf::from("/tmp/kon-test/models/llm")
+            PathBuf::from("/tmp/magnotia-test/models/llm")
         );
     }
 }