feat(web): retrofit drawers + CreateTopologyWizard with ESC/focus-trap

ArtifactDrawer, SessionDrawer, CreateTopologyWizard all now:
- close on ESC
- trap Tab/Shift+Tab focus within the panel
- lock body scroll while open
- restore prior focus on unmount

Uses the new useEscapeKey + useFocusTrap hooks. No visual changes;
the bespoke CSS shells (ctw-*, inline drawer styling) are preserved.

decnet_web/src/components/ArtifactDrawer.tsx

@@ -1,6 +1,8 @@
-import React, { useState } from 'react';
+import React, { useEffect, useRef, useState } from 'react';
 import { X, Download, AlertTriangle } from 'lucide-react';
 import api from '../utils/api';
+import { useEscapeKey } from '../hooks/useEscapeKey';
+import { useFocusTrap } from '../hooks/useFocusTrap';
 
 interface ArtifactDrawerProps {
   decky: string;
@@ -32,6 +34,15 @@ const Row: React.FC<{ label: string; value: React.ReactNode }> = ({ label, value
 );
 
 const ArtifactDrawer: React.FC<ArtifactDrawerProps> = ({ decky, storedAs, fields, onClose }) => {
+  const panelRef = useRef<HTMLDivElement | null>(null);
+  useEscapeKey(onClose, true);
+  useFocusTrap(panelRef, true);
+  useEffect(() => {
+    const prev = document.body.style.overflow;
+    document.body.style.overflow = 'hidden';
+    return () => { document.body.style.overflow = prev; };
+  }, []);
+
   const [downloading, setDownloading] = useState(false);
   const [error, setError] = useState<string | null>(null);
   const meta = decodeMeta(fields);
@@ -80,6 +91,9 @@ const ArtifactDrawer: React.FC<ArtifactDrawerProps> = ({ decky, storedAs, fields
       }}
     >
       <div
+        ref={panelRef}
+        role="dialog"
+        aria-modal="true"
         onClick={(e) => e.stopPropagation()}
         style={{
           width: 'min(620px, 100%)', height: '100%',

decnet_web/src/components/SessionDrawer.tsx

@@ -1,6 +1,8 @@
 import React, { useEffect, useRef, useState } from 'react';
 import { X, AlertTriangle } from 'lucide-react';
 import api from '../utils/api';
+import { useEscapeKey } from '../hooks/useEscapeKey';
+import { useFocusTrap } from '../hooks/useFocusTrap';
 // @ts-expect-error -- ships without type defs; 3.x CJS build is used directly
 import * as AsciinemaPlayer from 'asciinema-player';
 import 'asciinema-player/dist/bundle/asciinema-player.css';
@@ -46,6 +48,15 @@ function buildCastBlob(header: Record<string, any>, events: [number, string, str
 }
 
 const SessionDrawer: React.FC<SessionDrawerProps> = ({ decky, sid, fields, onClose }) => {
+  const panelRef = useRef<HTMLDivElement | null>(null);
+  useEscapeKey(onClose, true);
+  useFocusTrap(panelRef, true);
+  useEffect(() => {
+    const prev = document.body.style.overflow;
+    document.body.style.overflow = 'hidden';
+    return () => { document.body.style.overflow = prev; };
+  }, []);
+
   const [header, setHeader] = useState<Record<string, any> | null>(null);
   const [events, setEvents] = useState<[number, string, string][]>([]);
   const [loading, setLoading] = useState(true);
@@ -145,6 +156,9 @@ const SessionDrawer: React.FC<SessionDrawerProps> = ({ decky, sid, fields, onClo
       }}
     >
       <div
+        ref={panelRef}
+        role="dialog"
+        aria-modal="true"
         onClick={(e) => e.stopPropagation()}
         style={{
           width: 'min(920px, 100%)', height: '100%',

decnet_web/src/components/TopologyList/CreateTopologyWizard.tsx

@@ -1,6 +1,8 @@
-import React, { useCallback, useEffect, useMemo, useState } from 'react';
+import React, { useCallback, useEffect, useMemo, useRef, useState } from 'react';
 import { X, Server, Cpu, FileText, Sparkles, Check } from 'lucide-react';
 import api from '../../utils/api';
+import { useEscapeKey } from '../../hooks/useEscapeKey';
+import { useFocusTrap } from '../../hooks/useFocusTrap';
 import './CreateTopologyWizard.css';
 
 /* Shape of GET /swarm/hosts rows (mirrors SwarmHostView). */
@@ -36,6 +38,17 @@ interface Props {
 const LOCAL_CARD_ID = '__local__';
 
 const CreateTopologyWizard: React.FC<Props> = ({ open, onClose, onCreated }) => {
+  const panelRef = useRef<HTMLDivElement | null>(null);
+  useEscapeKey(onClose, open);
+  useFocusTrap(panelRef, open);
+
+  useEffect(() => {
+    if (!open) return;
+    const prev = document.body.style.overflow;
+    document.body.style.overflow = 'hidden';
+    return () => { document.body.style.overflow = prev; };
+  }, [open]);
+
   const [step, setStep] = useState<0 | 1>(0);
   const [targetId, setTargetId] = useState<string | null>(null); // LOCAL_CARD_ID or host uuid
   const [kind, setKind] = useState<Kind | null>(null);
@@ -228,7 +241,7 @@ const CreateTopologyWizard: React.FC<Props> = ({ open, onClose, onCreated }) =>
 
   return (
     <div className="ctw-backdrop" onClick={onClose}>
-      <div className="ctw-modal" onClick={(e) => e.stopPropagation()}>
+      <div className="ctw-modal" ref={panelRef} role="dialog" aria-modal="true" onClick={(e) => e.stopPropagation()}>
         <div className="ctw-head">
           <h3>
             <Sparkles size={14} style={{ marginRight: 8 }} /> NEW TOPOLOGY