fix: remove tauri-plugin-log to avoid logger conflict

`tracing_subscriber::fmt().try_init()` installs a global log
implementation via the tracing-log shim. tauri-plugin-log then
calls `log::set_logger()` which panics with "attempted to set a
logger after the logging system was already initialized".

The plugin was never wired in JS code (no @tauri-apps/plugin-log
import) — backend logging via tracing is sufficient. Drop:
  - tauri-plugin-log dep + plugin registration
  - log:default capability permission
  - @tauri-apps/plugin-log JS dep

Verified: cargo check is clean, app starts past the panic.

package.json

@@ -13,7 +13,6 @@
   "dependencies": {
     "@tauri-apps/api": "^2.2.0",
     "@tauri-apps/plugin-dialog": "^2.2.0",
-    "@tauri-apps/plugin-log": "^2.2.0",
     "@tauri-apps/plugin-shell": "^2.2.0",
     "@tauri-apps/plugin-store": "^2.2.0",
     "class-variance-authority": "^0.7.1",