Fix multiple windows and tabs support

[Yaraslaut]

closes #1725
closes #1728
closes #1729
closes #1730

[Copilot]

Copilot reviewed 10 out of 11 changed files in this pull request and generated 2 comments.

Files not reviewed (1)

• metainfo.xml: Language not supported

[christianparpart]

one thing I've committed and pushed right away, but some more comments I still wanted to leave :)

[Copilot]

Pull Request Overview

This PR implements support for multiple windows and tabs by tracking sessions per display, adding handlers to properly close sessions on window close or termination, and introduces atomic flags to coordinate session creation and switching.

• Add onClosing QML handler to remove a session when its window closes
• Update termination logic to choose between closing a window or a tab via canCloseWindow()
• Implement a displayStates map in TerminalSessionManager to manage sessions per display

Reviewed Changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/contour/ui/main.qml	Added onClosing handler to call terminalSessions.closeWindow()
src/contour/ui/Terminal.qml	Changed onTerminated to use canCloseWindow() for window vs tab
src/contour/display/TerminalDisplay.h	Removed outdated comment about single-terminal limitation
src/contour/display/TerminalDisplay.cpp	Notify session manager on focus-in event
src/contour/TerminalSessionManager.h	Added displayStates, closeWindow, canCloseWindow, etc.
src/contour/TerminalSessionManager.cpp	Major multi-display/session logic, focus management, and closing
src/contour/TerminalSession.h	Exposed getTerminalManager()
src/contour/TerminalSession.cpp	Notify manager on session termination and coordinate new tabs
src/contour/ContourGuiApp.cpp	Removed direct display assignment in newWindow()
metainfo.xml	Documented the multiple windows/tabs fix
CMakeLists.txt	Added /bigobj compile flag for MSVC
.github/actions/spelling/allow/uncategorized.txt	Allowed bigobj in spelling whitelist

Comments suppressed due to low confidence (3)

src/contour/TerminalSessionManager.h:59

• [nitpick] Method name FocusOnDisplay uses uppercase first letter, but other methods use lowerCamelCase. Rename it to focusOnDisplay for consistency.

void FocusOnDisplay(display::TerminalDisplay* display);

src/contour/TerminalSessionManager.cpp:384

• New logic in tryFindSessionForDisplayOrClose and window/tab management is complex; consider adding unit tests to cover behavior when sessions equal, exceed, or are fewer than displays.

void TerminalSessionManager::tryFindSessionForDisplayOrClose()

src/contour/ui/Terminal.qml:199

• The else branch for closing a tab was removed; if canCloseWindow() is false, nothing happens. Restore or add a fallback to call terminalSessions.closeTab().

if (terminalSessions.canCloseWindow())

[Yaraslaut]

I tested this on windows and it is save to use in release build, debug might throw here and there issues because of the state verification but this is timing issues with windows and we check it on linux more thoughtful

[christianparpart]

Let's do this! 😄