fix(gui): create the state dir before the tray and app use it (B194)

On a fresh install only the daemon and the CLI created
~/.local/state/proton-drive-linux. The app starts the tray before the
first sign-in, so the tray failed to bind its single-instance socket and
exited, and the Takeout page could not remember staged archives (#29).

- gui: pdfs-tray and pdfs-app call AppDirs::ensure at start, which also
  makes the directories owner-only
- docs: B194 in the bug ledger, changelog entry

docs/CHANGELOG.md

@@ -11,6 +11,12 @@ scratch (user data in `staging/` and `recovery/` is never touched by this).
 
 ## [Unreleased]
 
+### Fixed
+- **On a fresh install the tray icon did not start.** The tray and the app now create their state
+  directory themselves instead of waiting for the service to do it. This also lets the Takeout
+  page remember staged archives before the first mount.
+  ([#29](https://github.com/narrrl/proton-drive-linux/issues/29))
+
 ## [3.1.1] — 2026-10-07
 
 Schema: **42**, unchanged.