StoreSession breaks on Windows when sessionName is an absolute path

[Minecraft9101010]

On Windows, StoreSession fails to load an existing session when sessionName is an absolute path (e.g. C:\Users\me.telegram\session). The cause is in gramjs/sessions/StoreSession.ts, in the constructor:

this.store = store.area(
sessionName,
new LocalStorage("./" + sessionName)
);
It unconditionally prepends "./" to sessionName. When the name is already an absolute path, this produces a malformed path like ./C:\Users\me.telegram\session, so node-localstorage reads/writes the wrong directory and the saved session is never found. The user gets logged out every run.

The fix is to only prepend "./" for relative paths:

const path = require("path");
this.store = store.area(
sessionName,
new LocalStorage(path.isAbsolute(sessionName) ? sessionName : "./" + sessionName)
);
(path can be hoisted to a top-of-file import if preferred.) This leaves the existing relative-path behavior untouched and fixes absolute paths on all platforms. Happy to open a PR if that's easier.