Bump version to v0.1.8 — Windows playtest fixes

- Fix switchAccount: check signer was set after loginWithNsec before
  returning; fall back to loginWithPubkey on silent failure; always
  navigate to feed after switch to clear stale UI
- Fix profile edit button: hidden in read-only (npub) mode; read-only
  badge shown in profile header to make state visible
- Sidebar: show version number (v0.1.8) below WRYSTR brand, auto-tracked
  from package.json — no more hardcoding
- Support page: increase QR code gap (gap-8 → gap-16) to prevent
  accidentally scanning the wrong address
- ROADMAP: add language/alphabet feed filter to Phase 3 backlog

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src-tauri/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "wrystr"
-version = "0.1.7"
+version = "0.1.8"
 description = "Cross-platform Nostr desktop client with Lightning integration"
 authors = ["hoornet"]
 edition = "2021"