feat(files): New → Clone repository clones into the open folder

The File Explorer's New menu (and its right-click menu) gains Clone
repository: it clones a URL into the folder it has open — of the user's own
home or of a workspace's own folder — through POST /api/lanes/clone with
that folder as `parent`, so the URL allowlist, the own-folder check and the
folder account's own git identity all apply, and opens a workspace on the
clone. ECREDENTIALS asks for a login, ESSHAUTH points to Settings → Git.
GET /api/homes now gives `me` its absolute `dir`. Keys typed in the dialog
never reach the explorer's shortcuts (Backspace / Delete).

docs/API.md

@@ -298,7 +298,7 @@ re-run.
 #### File Explorer on a home
 
 ```
-GET  /api/homes                                   { homes: [{ id: "me" | <username>, label, readOnly }] }
+GET  /api/homes                                   { homes: [{ id: "me" | <username>, label, readOnly, dir? }] }
 GET  /api/homes/:who/fs/list|trash|zip|download   as the workspace routes above
 POST /api/homes/:who/fs/mkdir|newfile|rename|move|copy|delete|upload|trash/restore|trash/purge
 ```
@@ -341,6 +341,13 @@ A copy goes home ↔ workspace
 one Linux account; each side is checked under its own rule. A home is never a
 workspace. The **Files** page opens on `?home=me` by default.
 
+`me` alone carries `dir`, its absolute folder: the File Explorer's **New →
+Clone repository** (`client/src/components/lanes/CloneHereDialog.tsx`) clones
+into the folder it has open — of the user's own home or of a workspace's own
+folder, never a session worktree, an extra folder or another user's home —
+through `POST /api/lanes/clone` below with that folder as `parent`, so every
+check of that route applies, and opens a workspace on the clone.
+
 #### Clone a repository into a new workspace
 
 ```