Close version modal when installation starts

[TyceHerrman]

Problem

After selecting a target version and clicking Switch to selected version, the modal remains open with a loading spinner until downloadUpdate() finishes.

The plugin can finish installing quickly, but downloadUpdate() then waits for a full update scan, making the installation appear stuck.

installPluginFromGithub() already displays a completion notice after installing and reloading the plugin. The modal displays another generic success notice only after the full scan finishes.

Expected behavior

• Close the version modal as soon as installation starts.
• Continue installation in the background.
• Keep the existing installation success and failure notices.
• Run the full update scan and manager refresh in the background.
• Remove the delayed duplicate success notice from the modal.

Reproduction

1. Open Plugin Manager → Updates.
2. Click a target version.
3. Click Switch to selected version.
4. Observe the modal remaining open throughout the subsequent update scan.

Tested with Better Manager 1.0.14 and Obsidian 1.13.4.