v4.2.0: wire the GUI to the core, transport and all four games

Phase 4. The egui frontend now shares ClientCore and the client database with the terminal: one background worker owns TLS, trust answers go through a channel, and a 10 s request deadline mirrors the terminal socket timeout. First contact, a changed key and a version mismatch are explicit screens; login can remember the credential and auto-login signs in before the login form appears.

Adds the lobby with an update notice, a full-width scrollable history table, and the four games painted from View: slots with reel animation and win lines that stop at the last matching reel, roulette with the hover lattice and wheel spin, blackjack with vector-drawn suits, and a smooth crash curve. Sidebars pin their action block; leaving a live hand or round asks before forfeiting.

The header balance holds the staked amount while the reels or wheel turn and only shows the payout when they stop. Refused spins cancel the animation. Live crash multipliers keep full precision for the chart; the terminal still displays two decimals.

Verified live against a 4.2.0 server: register, login, auto-login, trust, all four games settling, history (50 rows), logout, disconnect, forfeit confirmation, and the version-mismatch screen. Release: 8.3 MB Linux, 6.8 MB Windows, 61 ms to window, 131 MB idle RSS.

1 files changed, 55 insertions, 16 deletions

diff --git a/docs/GUI-PLAN.md b/docs/GUI-PLAN.md
index bb63530..4279626 100644
--- a/docs/GUI-PLAN.md
+++ b/docs/GUI-PLAN.md
@@ -67,9 +67,7 @@ crash board from its local clock.
 
 **Gate:** all four games playable in the TUI through `Command`/`View`.
 
-## Phase 3 — `gui/` skeleton and the style spike
-
-**Code complete in v4.1.0; awaiting the screenshot sign-off.**
+## Phase 3 — `gui/` skeleton and the style spike (done)
 
 - `gui/` is a workspace member (`zagan-bet-gui`). It depends on the core with
   `default-features = false`, so neither egui nor native-tls enters the TUI or
@@ -104,24 +102,65 @@ Measured on Linux at 1080p with llvmpipe software GL:
 | Idle RSS | 137 MB |
 | Idle CPU | 0% |
 
-The approved reference lives at `docs/screenshots/gui-roulette-1080p.png`, with
-the result state at `docs/screenshots/gui-roulette-result-1080p.png`.
-
-**Gate:** the screenshot needs your approval. Frame rate on integrated graphics
-still needs a run on real hardware.
+The Phase 4 screenshots in `docs/screenshots/` supersede the spike captures;
+they show the same layout with the real session and the pinned action bars.
+
+**Gate:** met. The style was approved and the spike grew into Phase 4.
+
+## Phase 4 — GUI wiring (code complete, v4.2.0)
+
+- `gui/src/net.rs` is the adapter's network worker. One blocking thread owns the
+  TLS stream; `Command` goes in, `Event` comes out (connected, failed, trust,
+  line, closed), and every event calls `Context::request_repaint`. There is no
+  async runtime.
+- First contact is a modal that answers the transport's trust callback through
+  a channel. A changed key is a hard stop with an explicit forget-and-retry;
+  a version mismatch links to the download page; a saved credential auto-logs
+  in before the login screen is ever shown.
+- Screens: connect (remembered hosts, forget trust), login/register with a
+  "remember this login" choice, lobby with the update notice, history table,
+  and the four games. "Log out" and "forget saved login" are separate. Leaving
+  a live hand or round asks first and forfeits the reservation.
+- Games are painted from `View`: slots with a 0.9 s reel animation and payline
+  highlights, roulette with the wheel spin, the hover lattice, chip placement
+  and payouts, blackjack with vector-drawn suits and legal actions, crash with
+  a sampled curve, cashout and a server-drawn crash point. A refused spin shows
+  the error and never runs the animation: the reels and the wheel wait for the
+  server's answer, not for the click.
+- Sidebars pin their action block below the content, so SPIN, CLEAR, DEAL and
+  START never move as the bet slip or a hand grows. The embedded fonts have no
+  suit or arrow glyphs, so suits are shapes and navigation uses plain words.
+- The header balance is held at the staked amount while the reels or wheel
+  turn, then jumps to the settled value: the GUI never reveals a payout before
+  the animation does. Refused spins cancel the animation and show the error.
+  The crash multiplier keeps full precision in the game state so the chart is
+  a smooth line; the terminal still formats it to two decimals.
+- `gui/tests/layout.rs` covers money, wheel angles, lattice snapping, table
+  aspect and bet names.
+
+Verified live against a v4.2.0 server: register, login, auto-login, trust,
+all four games settling, history, logout, disconnect, the leave-forfeit
+confirmation, and the version-mismatch screen (new client against a 4.1.1
+server).
+
+Screenshots: `docs/screenshots/gui-{lobby,slots,roulette,blackjack,crash,
+history}-1080p.png`, plus the roulette result state.
 
-## Phase 4 — GUI wiring
-## Phase 4 — GUI wiring
+Measured on Linux at 1080p with llvmpipe software GL:
 
-- Network thread with channels, request deadlines in the shared adapter.
-- Trust modal, version-mismatch screen, login/register, lobby, history panel.
-- All four games, per-frame painting and tier 1–2 effects.
-- Update notice from the handshake in the lobby.
+| Check | Result |
+| --- | --- |
+| Linux binary | 8.3 MB |
+| Windows x86_64 binary | 6.8 MB |
+| Cold start to window | 61 ms |
+| Idle RSS | 131 MB |
+| Idle CPU | 0% |
 
-**Gate:** manual checklist per game at 60 fps, `egui_kittest` wiring tests,
-modem-throttled run.
+**Gate:** the screenshot set is ready for review. Remaining for the gate:
+frame rate on integrated graphics and the Windows interactive pass.
 
 ## Phase 5 — packaging
+## Phase 5 — packaging
 
 - `publish.sh` emits `zagan-bet-gui-<version>-<platform>-<arch>[.exe]`.
 - Bash and PowerShell installers that verify the SHA-256, install to the user