fix(capture/win-display): a deactivated laptop panel is a named stall suspect, not a blind spot

Field A/B (reporter, Legion 5 Pro hybrid, 2026-07-27): the ~2 s capture-stall
metronome IS the exclusive isolate's own doing — deactivating the laptop panel
leaves a dark-but-connected eDP head whose driver-level servicing disturbs the
capture path (~1.7-2.8 s period); `topology: primary` (panel stays active)
stopped it outright (16.3 stalls/min → 0). Our own .221 logged the identical
signature the day before. The detector then steered AWAY from the cause:
connected_inactive filtered to EXTERNAL physicals only, so the one display
that mattered — on a hybrid laptop, the default config — reported as `none`.

- TargetInventory: new `internal_panel` class bit (eDP/LVDS/embedded).
- connected_inactive_externals → connected_inactive_physicals: internal
  panels join the suspect list (virtual/indirect stay excluded); a nameless
  panel renders as "laptop panel".
- The below-OS METRONOMIC warn names the dark-panel case and its actual
  cures (`topology: primary`, `pnp_disable_monitors`) — the old text's
  "unplug it" prescriptions are impossible for an internal panel.
- ddc_power_off: a zero-ack sweep now says at INFO that the axis did nothing
  (internal panels have no DDC/CI) instead of silently no-op'ing.

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

crates/pf-vdisplay/src/vdisplay/ddc.rs

@@ -181,9 +181,14 @@ pub fn panel_off_except(exclude_gdi: &str) -> u32 {
         acked += set_power(m.hmon, &m.device, POWER_OFF);
     }
     if acked == 0 {
-        tracing::debug!(
-            "DDC/CI: no physical panel accepted the DPMS-off command \
-             (no DDC/CI-capable panel besides the virtual display)"
+        // INFO, not debug: the user opted into this axis, so "it did nothing" is an answer they
+        // asked for. The common case is a laptop — internal eDP/LVDS panels have NO DDC/CI at
+        // all (their brightness/power runs over the driver's own channel), so `ddc_power_off`
+        // is structurally a no-op for them (reporter feedback 2026-07-27).
+        tracing::info!(
+            "DDC/CI: no panel accepted the DPMS-off command — the ddc_power_off axis did \
+             nothing on this display set (internal eDP/LVDS panels expose no DDC/CI; external \
+             monitors may have it disabled in the OSD or dropped by a dock/KVM)"
         );
     }
     acked