* feat(env): allow setting the initial URI path for the web panel
* fix(setting): normalize and guard XUI_INIT_WEB_BASE_PATH default
Address Copilot review on PR #5149: an env value that is empty, whitespace, or lacks slashes (e.g. `panel`) could produce an invalid webBasePath such as `/ /` and reach the frontend un-normalized.
getEnv now trims whitespace and falls back when the value is empty; the env-derived default is passed through the existing normalizeBasePath helper (reused from node.go) so it always carries a leading and trailing slash. GetBasePath reuses the same helper instead of duplicating the slash logic.
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Co-authored-by: Sanaei <ho3ein.sanaei@gmail.com>
