Ask doctor and devices about the programs this system actually uses

`doctor` had the Wayland pair spelled into it, so an X11 machine was never
asked about the two it really pastes with, a Mac was told ydotool and
kwriteconfig6 were missing, and Windows, which shells out for neither half of
the clipboard, got five red marks for programs it was never going to have. The
two come out of `paste.Desktop` now, and the Linux-only three are added on
Linux. A row saying a program is missing on a machine that would never have run
it is not a diagnosis, it is a mark to explain away.

`devices` had the same shape of answer: "pactl found nothing; is PipeWire
running?" on a Windows machine with no microphone. It names whatever this sound
system is missing instead, which is the string the table already carries for it.

The Windows README's troubleshooting sends people to both, so it says so.

cli.py

@@ -655,7 +655,10 @@ def cmd_devices(opts):
                  "default": name == default}
                 for name, desc in audio.list_monitors()]
     if not mics and not monitors:
-        return fail(opts, "pactl found nothing; is PipeWire running?")
+        # Which program was asked, and so which one to go and look at, is not
+        # the same on all four systems: naming pactl on Windows sends somebody
+        # after a program that was never going to be there.
+        return fail(opts, audio.sound().missing)
 
     lines = ["Microphones:"]
     lines += [f"  {'*' if item['chosen'] else ' '} {item['name']}\n"
@@ -791,9 +794,20 @@ def cmd_status(opts):
 def cmd_doctor(opts):
     """What the settings window checks behind its buttons, in one pass."""
     conf = cfg.Config()
-    wanted = ["pw-record", "wl-copy", "ydotool", "ffmpeg", "pactl", "kwriteconfig6",
-              assistant.executable(assistant.provider(conf)) or "claude",
-              cleanup.executable(cleanup.provider(conf))]
+    # The two the clipboard and the key press go through come out of the table
+    # rather than being spelled here, because they are not the same pair on all
+    # four systems: X11 pastes with xclip where Wayland pastes with wl-copy, a
+    # Mac shells out for one half and Windows for neither. A row saying ydotool
+    # is missing on a machine that would never have run it is not a diagnosis,
+    # it is a red mark to explain away.
+    here = paste.desktop()
+    wanted = [here.clipboard, here.keyboard]
+    if sys.platform.startswith("linux"):
+        # Recording, the device list, and KDE's shortcut registry.
+        wanted += ["pw-record", "pactl", "kwriteconfig6"]
+    wanted += ["ffmpeg",
+               assistant.executable(assistant.provider(conf)) or "claude",
+               cleanup.executable(cleanup.provider(conf))]
     programs = {name: shutil.which(name) or "" for name in wanted if name}
     target = conf.transcribe_target()
     cleaner = cleanup.provider(conf)