feat: Delphi backend + JS↔Delphi bridge (clipboard, tray, auto-lock)

Introduces the Delphi 12 FMX backend (PMServer) that hosts the embedded
WebView2 vault on 127.0.0.1, and a native bridge between JS and Delphi
that wires three privacy-focused features:

1. Secure clipboard
   Copying a password registers the Win32 "ExcludeClipboardContentFromMonitorProcessing"
   format alongside CF_UNICODETEXT, so Win+V clipboard history never sees
   the value. Auto-clears after 30s via TTimer. Bridge.copySecure() in
   app.js routes all password/username/secret copy paths through the
   native layer when running inside the Delphi WebView2 (falls back to
   navigator.clipboard for the PHP standalone).

2. Tray icon (X-to-tray when server running)
   Closing the dev panel hides both the form HWND and the TFMAppClass
   per-process proxy window that owns the FMX taskbar entry — the form's
   HWND alone is not the taskbar-visible one in FMX (took some iteration
   to discover). Tray menu: Open, Lock vault, Quit. Clipboard is force-
   cleared on minimize as extra safety. First-time minimize fires a
   balloon notification so the user knows the app is still running.

3. Auto-lock on Windows session lock (Win+L)
   wtsapi32.dll!WTSRegisterSessionNotification on a dedicated message-only
   window. On WM_WTSSESSION_CHANGE / WTS_SESSION_LOCK, the bridge calls
   ExecuteJavaScript('lockVault()'). Same path used by the tray "Lock vault"
   menu item.

Bridge architecture:
 - JS → Delphi via cmd:// URLs intercepted in OnBeforeNavigate
   (pattern lifted from DeskInsight Monaco). Currently exposes
   cmd://clipboard/copy?text=...&clear=... and cmd://clipboard/clear.
 - Delphi → JS via TTMSFNCWebBrowser.ExecuteJavaScript with guarded
   calls (typeof check) so the bridge degrades cleanly if app.js isn't
   loaded yet.

Files:
 - Source/PM.Bridge.pas (new) — TSecureClipboard + TPMBridge
 - UMainForm.pas/.fmx — bridge wiring, FormCloseQuery intercept, tray
   callbacks (BridgeTrayRestore / BridgeLockRequest / BridgeQuit)
 - js/app.js — Bridge object, 5 navigator.clipboard sites migrated to
   Bridge.copySecure with PHP-compatible fallback, Bridge.onTrayRestore
   handler that resets the auto-lock timer

.gitignore extended with Delphi build artifacts (*.dcu, Win32/, Win64/,
__history/, __recovery/, *.identcache, *.dsk, *.local, etc.) so source
checkouts stay clean.

delphi-backend/UMainForm.fmx

@@ -0,0 +1,133 @@
+object MainForm: TMainForm
+  Left = 0
+  Top = 0
+  Caption = 'Password Manager - Delphi Backend'
+  ClientHeight = 720
+  ClientWidth = 1100
+  FormFactor.Width = 320
+  FormFactor.Height = 480
+  FormFactor.Devices = [Desktop]
+  OnCreate = FormCreate
+  OnDestroy = FormDestroy
+  OnCloseQuery = FormCloseQuery
+  DesignerMasterStyle = 0
+  object PanelTop: TPanel
+    Align = Top
+    Size.Width = 1100.000000000000000000
+    Size.Height = 56.000000000000000000
+    Size.PlatformDefault = False
+    TabOrder = 0
+    object lblPort: TLabel
+      Position.X = 16.000000000000000000
+      Position.Y = 18.000000000000000000
+      Size.Width = 40.000000000000000000
+      Size.Height = 20.000000000000000000
+      Size.PlatformDefault = False
+      TextSettings.Trimming = None
+      Text = 'Port:'
+      TabOrder = 0
+    end
+    object edtPort: TEdit
+      Touch.InteractiveGestures = [LongTap, DoubleTap]
+      TabOrder = 1
+      Text = '8765'
+      Position.X = 56.000000000000000000
+      Position.Y = 14.000000000000000000
+      Size.Width = 80.000000000000000000
+      Size.Height = 24.000000000000000000
+      Size.PlatformDefault = False
+    end
+    object btnStart: TButton
+      Position.X = 152.000000000000000000
+      Position.Y = 14.000000000000000000
+      Size.Width = 80.000000000000000000
+      Size.Height = 24.000000000000000000
+      Size.PlatformDefault = False
+      TabOrder = 2
+      Text = 'Start'
+      TextSettings.Trimming = None
+      OnClick = btnStartClick
+    end
+    object btnStop: TButton
+      Position.X = 240.000000000000000000
+      Position.Y = 14.000000000000000000
+      Size.Width = 80.000000000000000000
+      Size.Height = 24.000000000000000000
+      Size.PlatformDefault = False
+      TabOrder = 3
+      Text = 'Stop'
+      TextSettings.Trimming = None
+      OnClick = btnStopClick
+    end
+    object btnReload: TButton
+      Position.X = 328.000000000000000000
+      Position.Y = 14.000000000000000000
+      Size.Width = 80.000000000000000000
+      Size.Height = 24.000000000000000000
+      Size.PlatformDefault = False
+      TabOrder = 4
+      Text = 'Reload'
+      TextSettings.Trimming = None
+      OnClick = btnReloadClick
+    end
+    object btnToggleLog: TButton
+      Position.X = 416.000000000000000000
+      Position.Y = 14.000000000000000000
+      Size.Width = 90.000000000000000000
+      Size.Height = 24.000000000000000000
+      Size.PlatformDefault = False
+      TabOrder = 5
+      Text = 'Hide log'
+      TextSettings.Trimming = None
+      OnClick = btnToggleLogClick
+    end
+    object lblStatus: TLabel
+      Position.X = 520.000000000000000000
+      Position.Y = 18.000000000000000000
+      Size.Width = 560.000000000000000000
+      Size.Height = 20.000000000000000000
+      Size.PlatformDefault = False
+      TextSettings.Trimming = None
+      Text = 'Stopped'
+      TabOrder = 6
+    end
+  end
+  object PanelLog: TPanel
+    Align = Bottom
+    Position.Y = 564.000000000000000000
+    Size.Width = 1100.000000000000000000
+    Size.Height = 156.000000000000000000
+    Size.PlatformDefault = False
+    TabOrder = 1
+    object Memo: TMemo
+      Touch.InteractiveGestures = [Pan, LongTap, DoubleTap]
+      DataDetectorTypes = []
+      ReadOnly = True
+      TextSettings.Font.Family = 'Consolas'
+      Align = Client
+      Size.Width = 1100.000000000000000000
+      Size.Height = 156.000000000000000000
+      Size.PlatformDefault = False
+      TabOrder = 0
+      Viewport.Width = 1096.000000000000000000
+      Viewport.Height = 152.000000000000000000
+    end
+  end
+  object Splitter: TSplitter
+    Align = Bottom
+    Cursor = crVSplit
+    MinSize = 20.000000000000000000
+    Position.Y = 558.000000000000000000
+    Size.Width = 1100.000000000000000000
+    Size.Height = 6.000000000000000000
+    Size.PlatformDefault = False
+  end
+  object WebBrowser: TTMSFNCWebBrowser
+    Align = Client
+    Size.Width = 1100.000000000000000000
+    Size.Height = 502.000000000000000000
+    Size.PlatformDefault = False
+    TabOrder = 3
+    DesigntimeEnabled = False
+  end
+end