dsh-hot-installer: Restart-free Add, Remove, and Hot Update for DeepSeek Harness Plugins

dsh-hot-installer is a DeepSeek Harness (DSH) plugin maintained by KYinCode and released under the MIT license. It aims to address the issue in DSH where adding, removing, or updating plugins requires a restart, making it particularly suitable for developers of long-lived surfaces (such as dsh web). This plugin monitors plugin manifest changes within the persistent profile, enabling hot-loading, hot-unloading, and hot-updating. It instantly modifies the running plugin tree without writing to configuration files or altering the patch layer throughout the process. Core features include: * Automatically mounting new packages and injecting patch files; * Removing corresponding plugin lines based on mapping; * Reloading immediately during upgrades; * Featuring a patch layer protection mechanism that automatically restores hot-loading lines upon manual editing conflicts (unless explicitly disabled); * Performing pre-checks and rolling back to the previous version upon upgrade failure; * Supporting self-updating without restart (v0.4.4+).