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.

src-tauri/src/commands/tasks.rs

@@ -1,4 +1,4 @@
-// Tauri commands wrapping kon_storage task CRUD.
+// Tauri commands wrapping magnotia_storage task CRUD.
 // Pattern mirrors transcripts.rs — TaskDto is the camelCase frontend shape,
 // storage functions are aliased with db_ prefix to avoid name collisions.
 
@@ -6,8 +6,8 @@ use serde::{Deserialize, Serialize};
 
 use uuid::Uuid;
 
-use kon_llm::prompts::FeedbackExample as LlmFeedbackExample;
-use kon_storage::{
+use magnotia_llm::prompts::FeedbackExample as LlmFeedbackExample;
+use magnotia_storage::{
     complete_subtask_and_check_parent as db_complete_subtask, complete_task as db_complete_task,
     delete_task as db_delete_task, get_task_by_id as db_get_task,
     insert_subtask as db_insert_subtask, insert_task as db_insert_task,