359e09fd65
Adds a reviewable in-app install path for Hermes plugins: hermes://plugin/install?repo=owner/repo (and Settings -> Plugins -> Install from Git) opens a confirmation modal showing the repo identity and source links, shallow-clones to probe for agent and/or desktop plugin artifacts, lets the user pick components, then installs — agent side through the gateway's new plugins.manage `install` action (wrapping the existing dashboard_install_plugin), desktop side through a new Electron git-install module with subdir-escape guards, a 60s clone timeout, non-interactive git env, and insecure-scheme warnings. Never auto-installs; hybrid repos get one dialog. Legacy plugin-agent / plugin-desktop deeplinks route into the same modal. Salvaged from PR #82735 by @serefyarar (net diff applied onto current main as a single authored commit; the branch carried merge commits). The preview screenshot PNG from the original branch was intentionally not carried over — images live in PR bodies, not the repo.