gui: real RTL + no-download-logic checks; split into velox-gui-lib

Follow-up hardening after a review noted the RTL "check" verified nothing
(a .ts stub that no test loads), matching a session-wide pattern of
checks written against what should be true rather than what would break.

- Split the non-main() code into velox-gui-lib (STATIC) so tests link the
  real widgets/models, not a reimplementation.
- tst_rtl: builds the real MainWindow, flips layoutDirection, asserts the
  direction propagates to the central widget AND that the offline-banner
  QHBoxLayout actually mirrors (label x-position LTR vs RTL differs by
  >100px). Verified it fails when the banner is pinned LtR.
- gui_no_download_logic: a ctest that greps gui/src for curl_*/pwrite/
  sqlite/QSqlDatabase/QNetworkAccessManager and fails on a hit — CLAUDE.md
  §3 as an executable check. Verified it fails when a curl_ token is added.
- Still uncovered (noted, not claimed): that the translation catalogue
  loads and the right context/strings resolve at runtime.

Not covered here because the files are PKG/QA-owned: tools/bootstrap.sh
ships a package name that does not exist on 26.04 (libqt6svg6-dev; the
real one is qt6-svg-dev), and --check validates pkg-config outcomes
rather than the apt names it would install. Both, plus the same name in
AGENT-PKG-QA.md and the README, are written up apply-ready in
gui/docs/pkg-qa-requests-m1.md.

Co-Authored-By: Claude Sonnet 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_016Ne28kx4VreeBWZv82Nksd

gui/CMakeLists.txt

@@ -1,24 +1,24 @@
 # velox-gui — the Qt 6 Widgets client. Lane GUI.
 #
 # CLAUDE.md §3: zero download logic here. This target links libveloxproto (the wire
-# types, ADR 0009) and NEVER libveloxcore — a grep for curl|pwrite|sqlite under gui/
-# must come back empty.
+# types, ADR 0009) and NEVER libveloxcore — enforced by tests/ (see the
+# gui_no_download_logic test).
 #
 # The root CMakeLists.txt add_subdirectory()s this unconditionally once the file exists,
-# so it must stay configurable even before CORE has landed veloxproto. Until that target
-# exists we announce and bail; the moment `core/` merges its libveloxproto, the GUI
-# lights up with no edit here (same contract as the root file's EXISTS() guards).
+# so it must stay configurable even if veloxproto is ever absent again. Until that target
+# exists we announce and bail.
 
 if(NOT TARGET veloxproto)
-    message(STATUS "velox-gui: libveloxproto has not landed yet — GUI target skipped. "
-                   "It builds automatically once core/ merges the veloxproto target (ADR 0009).")
+    message(STATUS "velox-gui: libveloxproto target missing — GUI target skipped. "
+                   "It builds automatically once core/ provides the veloxproto target (ADR 0009).")
     return()
 endif()
 
 set(CMAKE_AUTOMOC ON)
 
-add_executable(velox-gui
-    src/main.cpp
+# Everything except main() lives in a static lib so the tests can link the real widgets
+# and models rather than a reimplementation.
+add_library(velox-gui-lib STATIC
     src/rpc/RpcConnection.cpp
     src/rpc/RpcClient.cpp
     src/models/DownloadTableModel.cpp
@@ -26,29 +26,25 @@ add_executable(velox-gui
     src/mainwindow/MainWindow.cpp
 )
 
-target_include_directories(velox-gui PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src)
-
-target_compile_features(velox-gui PRIVATE cxx_std_23)
-
-# Warnings at target scope, not via CMAKE_CXX_FLAGS — the dev/tsan presets overwrite that
-# cache variable wholesale (same rationale as core/CMakeLists.txt).
-target_compile_options(velox-gui PRIVATE -Wall -Wextra -Wpedantic -Werror)
-
-target_link_libraries(velox-gui PRIVATE
+target_include_directories(velox-gui-lib PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/src)
+target_compile_features(velox-gui-lib PUBLIC cxx_std_23)
+target_compile_options(velox-gui-lib PRIVATE -Wall -Wextra -Wpedantic -Werror)
+target_link_libraries(velox-gui-lib PUBLIC
     velox::proto
     Qt6::Widgets
     Qt6::Svg
     Qt6::Network
 )
 
-set_target_properties(velox-gui PROPERTIES
-    WIN32_EXECUTABLE OFF
-    MACOSX_BUNDLE OFF
-)
+add_executable(velox-gui src/main.cpp)
+target_compile_options(velox-gui PRIVATE -Wall -Wextra -Wpedantic -Werror)
+target_link_libraries(velox-gui PRIVATE velox-gui-lib)
+set_target_properties(velox-gui PROPERTIES WIN32_EXECUTABLE OFF MACOSX_BUNDLE OFF)
 
 # --- i18n -------------------------------------------------------------------------------
 # Every string in the GUI goes through tr(); the Arabic stub exists to prove the RTL
-# layout survives (GUI DoD). lrelease/lupdate come from Qt6::LinguistTools, found by root.
+# layout survives (GUI DoD), exercised by tests/tst_rtl. lrelease also drops the .qm at
+# ${CMAKE_CURRENT_BINARY_DIR}/velox_ar.qm, which the RTL test loads by path.
 qt_add_translations(velox-gui TS_FILES i18n/velox_ar.ts)
 
 # --- tests ---------------------------------------------------------------------------