fix(host): name the lid-closed/no-frames failure — display-write decode, console-session guard, driver-truth attach diagnostics

Field report (Windows laptop, lid closed, Tailscale): v0.12.0's activation
fix works — the pf-vdisplay target activates in ~200ms — but the session
still dies at the first-frame gate: 'driver_status=1 but no frame published
within 4s'. Triage showed three independent blind spots; this names all of
them at their source instead of guessing downstream:

- pf-win-display: decode ChangeDisplaySettingsExW failures (-1 FAILED — a
  display write rejected, the wrong/remote-session signature — vs -2 BADMODE,
  which the old 'mode not advertised?' text conflated), and WARN on every
  non-zero SetDisplayConfig rc in the CCD isolate even when verification
  passes vacuously (the lid-closed case: nothing else active, so the INFO
  swallowed rc=0x5 ERROR_ACCESS_DENIED while the load-bearing COMMIT_MODES →
  ASSIGN_SWAPCHAIN re-commit silently never applied). Access-denied rcs get
  the remedy appended (console session / installed service).

- host: console-session guard (interactive::console_session_mismatch) — a
  host outside the active console session (a hand-launched host after an RDP
  round-trip) fails every display write, reads the wrong session's GDI view,
  and its SendInput compose kicks go nowhere. Named ERROR at vdisplay
  acquire + appended to the first-frame timeout, instead of the misleading
  generic failure. (The idd_push diagnosis half of this landed in 9a36ea21;
  this commit adds the proto helpers + session guard it references, healing
  the windows-cfg build.)

- proto + driver: while OPENED, driver_status_detail now carries a live
  packed word (bit31 live-marker | offered 15-bit | mismatch-dropped 16-bit)
  maintained by the publisher, so the host's first-frame timeout can tell
  apart: never-attached (no swap-chain worker ran), attached-but-DWM-composed-
  zero-frames (undamaged/powered-off desktop, kicks blocked on the secure
  desktop), and composed-but-every-frame-mismatched (ring sized from a stale/
  foreign-session GDI mode). Zero layout change, old drivers read as 'no
  detail'; unit-tested pack/unpack in pf-driver-proto.

Verified on winbox: cargo check + clippy -p punktfunk-host -p pf-win-display
-p pf-driver-proto EXIT 0, drivers ws cargo check -p pf-vdisplay EXIT 0
(Version_Number=10.0.26100.0), cargo fmt --all --check clean; pf-driver-proto
tests 13/13 pass locally.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

crates/punktfunk-host/src/windows/interactive.rs

@@ -30,6 +30,27 @@ use windows::Win32::System::Threading::{
     CreateProcessAsUserW, CREATE_UNICODE_ENVIRONMENT, PROCESS_INFORMATION, STARTUPINFOW,
 };
 
+/// `Some((own_session, console_session))` when this process is NOT in the active console session —
+/// the state in which every display write (`SetDisplayConfig` / `ChangeDisplaySettingsExW`) fails
+/// `ERROR_ACCESS_DENIED`, GDI reads describe the wrong session's displays, and `SendInput` compose
+/// kicks go nowhere. Field signature: a hand-launched host whose session later went remote (an RDP
+/// round-trip) — the installed service relaunches the host when the console session moves, a
+/// hand-launched one stays trapped. `None` in the console session, and `None` when the check
+/// itself can't answer (no console session attached — boot / session transition — or the session
+/// query failed): the guard exists to NAME a known-bad state, so an unknown state stays quiet.
+pub fn console_session_mismatch() -> Option<(u32, u32)> {
+    use windows::Win32::System::RemoteDesktop::ProcessIdToSessionId;
+    use windows::Win32::System::Threading::GetCurrentProcessId;
+    let mut own: u32 = 0;
+    // SAFETY: `own` is a live local out-param for this synchronous call; no pointer escapes it.
+    if unsafe { ProcessIdToSessionId(GetCurrentProcessId(), &mut own) }.is_err() {
+        return None;
+    }
+    // SAFETY: takes no arguments and returns the console session id by value.
+    let console = unsafe { WTSGetActiveConsoleSessionId() };
+    (console != 0xFFFF_FFFF && own != console).then_some((own, console))
+}
+
 /// Spawn `cmdline` in the active console session, under the logged-in user's token, on the
 /// interactive desktop (`winsta0\default`). Returns the new process id.
 ///