docs: the desktop shell and what the merge changed

Five components become three, and the Theme symlink count with them. Two
new notes: a pragma Singleton in a subdirectory resolves through a plain
directory import with no qmldir, and Virsh.sampling gates only the stats
poll, not the lifecycle stream that keeps the tile correct while the page
is closed.

3 files changed, 20 insertions, 0 deletions

diff --git a/desktop/modules/mail/README.md b/desktop/modules/mail/README.md
index 34eaa53..022bdda 100644
--- a/desktop/modules/mail/README.md
+++ b/desktop/modules/mail/README.md
@@ -1,5 +1,12 @@
 # mail-overview
 
+> **Now the `mail` module of the `desktop/` shell.** It is no longer a
+> standalone component: start the shell with `qs -p desktop` and open the page
+> from the drawer, or deep-link with `qs -p desktop ipc call drawer open mail`.
+> The `mail-overview` paths below are historical, the scripts now live under
+> `desktop/modules/mail/`, and the waybar click uses `ipc call drawer open
+> mail`. See `desktop/README.md`.
+
 Unread mail across every account, as one waybar number and a drawer behind it.
 Clicking the icon opens the drawer; Escape or a click outside closes it.
 
diff --git a/desktop/modules/sound/README.md b/desktop/modules/sound/README.md
index f0a8313..d1c50fc 100644
--- a/desktop/modules/sound/README.md
+++ b/desktop/modules/sound/README.md
@@ -1,5 +1,12 @@
 # volume-osd
 
+> **Now the `sound` module of the `desktop/` shell.** It is no longer a
+> standalone component: start the shell with `qs -p desktop` and open the
+> module's page from the drawer, or deep-link with
+> `qs -p desktop ipc call drawer open sound`. The prose below predates the
+> merge and its standalone `volume-osd` commands are historical. See
+> `desktop/README.md`.
+
 An on-screen display for volume, covering both output (speakers) and input
 (microphone). It appears at the bottom of the screen when the level or mute
 state changes, and fades out 1.5 seconds later.
diff --git a/desktop/modules/vm/README.md b/desktop/modules/vm/README.md
index bcf12ac..03ad1b5 100644
--- a/desktop/modules/vm/README.md
+++ b/desktop/modules/vm/README.md
@@ -1,5 +1,11 @@
 # vm-manager
 
+> **Now the `vm` module of the `desktop/` shell.** It is no longer a
+> standalone component: start the shell with `qs -p desktop` and open the page
+> from the drawer, or deep-link with `qs -p desktop ipc call drawer open vm`.
+> The `vm-manager` paths and the `panel toggle` IPC below are historical. See
+> `desktop/README.md`.
+
 A drawer for libvirt virtual machines: state, live statistics, the actions
 that make sense in the current state, and the snapshot list. It replaces the
 menu half of `rofi-qemu.sh`, which could only ever show a list of strings.