Show fingerprint on lock screen and polkit, gated by lid state

Bring the fingerprint affordance to the Quickshell lock screen and polkit
dialog, matching what hyprlock did on master.

Lock screen: render the md-fingerprint glyph inside the password field's
right edge when a sensor is enrolled, reserving space so long passwords
never run under it.

Polkit dialog: show one method at a time. When a sensor is enrolled and
the reader is reachable, the dialog is just the centered fingerprint icon
(square card); the moment PAM asks for a password it switches to the
password field. Detects pam_fprintd anywhere in the auth stack now that a
gate can precede it.

Lid awareness: a closed lid means the reader is unreachable, so both
surfaces fall back to the password. polkit gets a pam_exec clamshell gate
(auth [success=1 default=ignore] before pam_fprintd) so a shut lid drops
straight to the password prompt instead of blocking on the reader for the
pam_fprintd timeout; the lock screen hides the icon and skips scanning.

The gate points at the fixed /usr/bin path the package always provides so
it survives switching between package installs and dev-link. A migration
adds the gate for existing fingerprint setups.

New helper omarchy-hw-laptop-closed (pure lid state); omarchy-hw-clamshell
now composes it with the external-monitor check.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

shell/plugins/polkit/PolkitAgent.qml

@@ -32,24 +32,34 @@ Item {
   property bool responseVisible: false
   property bool failed: false
   property bool errorFlash: false
-  property bool fingerprintFirst: false
+  // pam_fprintd appears in the polkit PAM stack (a sensor is enrolled).
+  property bool fingerprintConfigured: false
+  // Lid shut right now — the reader is physically unreachable, so we fall back
+  // to the password even when a sensor is enrolled. Refreshed per request.
+  property bool laptopClosed: false
   property int shakeOffset: 0
 
   readonly property bool dialogVisible: polkitAgent.isActive || closing
-  readonly property bool fingerprintWaiting: dialogVisible && !responseRequired && !submitted && (fingerprintFirst || promptLooksFingerprint(currentPrompt + " " + currentSupplementary))
-  readonly property int cardWidth: Math.min(Style.space(312), Math.max(Style.space(260), panel.width - Style.gapsOut * 2))
+  // We show one method at a time. Fingerprint owns the dialog while PAM is
+  // waiting on the reader (lid open, sensor enrolled); the moment PAM asks for
+  // a password — including immediately when the lid is shut and the clamshell
+  // gate skips pam_fprintd — we switch to the password field instead.
+  readonly property bool fingerprintMode: fingerprintConfigured && !laptopClosed && dialogVisible && !responseRequired && !submitted && !errorFlash
   readonly property int cardHeight: panel.height > 0 ? Math.min(fieldHeight + contentMargin * 2, panel.height - Style.gapsOut * 2) : fieldHeight + contentMargin * 2
-
-  function promptLooksFingerprint(text) {
-    return PolkitModel.promptLooksFingerprint(text)
-  }
+  // Password mode is a wide field; fingerprint mode collapses to a square that
+  // just frames the centered sensor icon.
+  readonly property int cardWidth: fingerprintMode ? cardHeight : Math.min(Style.space(312), Math.max(Style.space(260), panel.width - Style.gapsOut * 2))
 
   function authorizationLabel(message) {
     return PolkitModel.authorizationLabel(message)
   }
 
   function loadPamConfig(raw) {
-    fingerprintFirst = PolkitModel.fingerprintFirstFromPamConfig(raw)
+    fingerprintConfigured = PolkitModel.fingerprintConfiguredFromPamConfig(raw)
+  }
+
+  function refreshLidState() {
+    if (!laptopClosedProc.running) laptopClosedProc.running = true
   }
 
   function resetSnapshot() {
@@ -83,13 +93,16 @@ Item {
     closing = false
     submitted = false
     passwordInput.text = ""
+    refreshLidState()
     syncFromFlow()
     Qt.callLater(refocus)
   }
 
   function refocus() {
     if (!dialogVisible) return
-    if (fingerprintWaiting) keyCatcher.forceActiveFocus()
+    // In fingerprint mode there is no field to type into — park focus on the
+    // key catcher so Escape still cancels; otherwise focus the password field.
+    if (fingerprintMode) keyCatcher.forceActiveFocus()
     else passwordInput.forceActiveFocus()
   }
 
@@ -149,10 +162,17 @@ Item {
     watchChanges: true
     printErrors: false
     onLoaded: root.loadPamConfig(text())
-    onLoadFailed: root.fingerprintFirst = false
+    onLoadFailed: root.fingerprintConfigured = false
     onFileChanged: reload()
   }
 
+  Process {
+    id: laptopClosedProc
+    command: ["bash", "-c", "omarchy-hw-laptop-closed && echo closed || echo open"]
+    stdout: StdioCollector { id: laptopClosedOut; waitForEnd: true }
+    onExited: root.laptopClosed = String(laptopClosedOut.text || "").trim() === "closed"
+  }
+
   PolkitAgent {
     id: polkitAgent
     path: "/org/omarchy/PolkitAgent"
@@ -248,8 +268,22 @@ Item {
         }
       }
 
+      // Fingerprint mode shows just the sensor icon, centered and alone \u2014 no
+      // padlock, no field, no prompt text.
+      OpticalGlyph {
+        anchors.centerIn: parent
+        width: Math.round(root.fieldHeight * 0.7)
+        height: width
+        visible: root.fingerprintMode
+        text: "\udb80\ude37"
+        fontFamily: root.fontFamily
+        fontSize: Math.round(root.fieldHeight * 0.7)
+        color: root.errorFlash ? Color.polkit.textError : root.accent
+      }
+
       Row {
         id: cardRow
+        visible: !root.fingerprintMode
         anchors.fill: parent
         anchors.topMargin: card.contentTopInset
         anchors.rightMargin: card.contentRightInset
@@ -287,8 +321,7 @@ Item {
             color: root.errorFlash ? Color.polkit.textError : root.foreground
             cursorVisible: activeFocus && !root.submitted && !root.errorFlash
             readOnly: root.submitted || root.errorFlash
-            enabled: root.dialogVisible && !root.fingerprintWaiting
-            visible: !root.fingerprintWaiting
+            enabled: root.dialogVisible
             onAccepted: root.submitResponse()
             Keys.onPressed: function(event) {
               if (event.key === Qt.Key_Escape) {
@@ -308,7 +341,7 @@ Item {
             font.family: root.fontFamily
             font.pixelSize: Style.font.iconLarge
             elide: Text.ElideRight
-            visible: passwordInput.visible && passwordInput.text.length === 0
+            visible: passwordInput.text.length === 0
           }
 
           Rectangle {

shell/plugins/polkit/PolkitModel.js

@@ -3,13 +3,16 @@ function promptLooksFingerprint(text) {
   return s.indexOf("finger") !== -1 || s.indexOf("fprint") !== -1 || s.indexOf("swipe") !== -1
 }
 
-function fingerprintFirstFromPamConfig(raw) {
+function fingerprintConfiguredFromPamConfig(raw) {
+  // Fingerprint is available whenever pam_fprintd appears anywhere in the auth
+  // stack — it need not be the first module. A clamshell gate (pam_exec) may
+  // legitimately precede it to skip fingerprint while the lid is closed.
   var lines = String(raw || "").split("\n")
   for (var i = 0; i < lines.length; i++) {
     var line = lines[i].replace(/^\s+|\s+$/g, "")
     if (!line || line.charAt(0) === "#") continue
     if (!line.match(/^auth\s+/)) continue
-    return line.indexOf("pam_fprintd.so") !== -1
+    if (line.indexOf("pam_fprintd.so") !== -1) return true
   }
   return false
 }
@@ -23,7 +26,7 @@ function authorizationLabel(message) {
 if (typeof module !== "undefined") {
   module.exports = {
     promptLooksFingerprint: promptLooksFingerprint,
-    fingerprintFirstFromPamConfig: fingerprintFirstFromPamConfig,
+    fingerprintConfiguredFromPamConfig: fingerprintConfiguredFromPamConfig,
     authorizationLabel: authorizationLabel
   }
 }