Publish topic guides to the wiki and document tabbed windows

Publish the guides from this repository to the GitHub Wiki. Organize them into Usage, Configuration and Development, with 15 separate configuration topics and redirects for the former website guide URLs.

Add a tabbed-windows guide covering grouping, switching tabs and taking windows out. Document the scrolling indicator's defaults and limits, and link the guide from the README, shortcuts and IPC pages. Update from main, including the latest tabbed-layout changes.

Separate Activities setup, configuration and publishing documentation. Review the guide prose with the unslop skill, keeping existing examples and heading links. The wiki workflow uses GitHub's built-in token to publish documentation changes on main.

Validation:

- 20 documentation tests pass, including README links and Activities/tab-indicator field coverage.
- The publisher builds 46 wiki pages; the site build and Python syntax checks pass.
- All 115 code examples from main are preserved.
- The Python suite passes: 90 tests passed and 31 opt-in integration tests skipped, with the system GI module available.

docs/tabbed-windows.md

@@ -0,0 +1,77 @@
+# Tabbed windows
+
+Tabs keep several windows in the same space, with one visible at a time.
+
+## Create a group
+
+In scrolling layout, press **Super + [** to put the focused window in the column
+to its left, or the one to its right if there is no left neighbour. Press
+**Super + Shift + T** to turn that column into tabs. Press it again to return to
+stacked rows with their previous sizes.
+
+In tree layout, **Super + [** joins the focused window to a neighbour as a tab.
+Ferese looks left, right, up, then down for a window to join.
+
+If you want to choose the direction, bind `join-tab` to `left`, `right`, `up`, or
+`down`; see [Commands and bindings](configuration/bindings.md). In scrolling
+layout, this also turns the destination column into tabs, even when the two
+windows are already in the same column. The ordinary `consume` action keeps the
+destination column's stacked or tabbed choice.
+
+## Switch tabs
+
+| Shortcut | Action |
+| --- | --- |
+| Super + Ctrl + [ | Previous tab |
+| Super + Ctrl + ] | Next tab |
+| Super + J / K | Next / previous row or tab in a scrolling column |
+| Super + H / L | Previous / next scrolling column |
+
+The previous/next tab shortcuts wrap at either end of the group. Switching tabs
+in a scrolling column keeps its width and scroll position. Vertical resizing
+has no effect while the column is tabbed.
+
+In tree layout, click a title in the bar above the window to select it.
+Scrolling columns have a segmented rail on the left: click a segment, or hover
+over the rail to see a list of titles. You can click a title in that list too.
+The list stays open as you move between it and the rail. Scroll through it when
+there are too many titles to fit on screen.
+
+Keyboard tab switching briefly shows the selected tab's number and title near
+the top of the window, as `n/N · title`.
+
+## Take a window out
+
+Press **Super + ]** to move the focused tab into its own column or split, to the
+right of the group. You can also use the `leave-tab` action. Closing a window,
+making it floating, or moving it to another workspace removes it from the group.
+New windows open beside the group.
+
+Tab controls disappear when only one window remains, or when the selected window
+is maximized or fullscreen. Leave fullscreen before grouping or switching tabs;
+fullscreen belongs to the individual window. Switching between tree and scrolling
+layouts keeps all windows but separates the groups.
+
+## Indicator and appearance
+
+The scrolling rail and title list sit over the desktop without taking space from
+the window. By default, the rail sits in the left gap if there are at least 8
+logical pixels available; otherwise it sits just inside the window. Its click
+area is wider than the visible rail. On short windows, the segments shrink to fit.
+
+The rail uses the theme's accent for the selected tab. The title list follows the
+shell's colors, corner radius and opacity. To change its size, colors or keyboard
+feedback duration, see [Layout configuration](configuration/layout.md#tabbed-columns).
+That page also shows how to open new columns as tabs by default.
+
+## feresectl
+
+These commands work on the focused window:
+
+```sh
+feresectl toggle-column-tabbed
+feresectl join-tab left
+feresectl next-tab
+feresectl previous-tab
+feresectl leave-tab
+```