feat: Spark Workbench everywhere, autonomous Hadoop offload & LLM masking-aware

- Data Hub with Hadoop tab (HDFS/Iceberg browser, Spark, pipeline)
- Databricks-style Lakehouse Workbench (Trino engine, live exec matrix,
  materialize to Iceberg/S3); reused & embedded in every source-DB UI
- HDFS -> Kafka -> Spark -> Iceberg/S3 pipeline; WebHDFS hostname resolver
- Data Flow master pulse switch (Run/Pause/Stop) gating animated edges
- Data Custodian autonomous Hadoop offload loop (batch counterpart to CDC),
  pulsing source -> HDFS edges; toggle in Data Flow
- LLM now autonomously aware of all latest platform changes (live platform
  context) and enforces masking policy: never reveals masked PII, still
  answers helpfully with aggregates/explanations

ui/src/App.tsx

@@ -11,17 +11,14 @@ import { ChatDrawer } from './components/features/ChatDrawer'
 import { GpuMonitor } from './components/features/GpuMonitor'
 import { InfraQuickAccess } from './components/features/InfraQuickAccess'
 import { InspectorPanel } from './components/features/InspectorPanel'
-import { PlatformTopology } from './components/features/PlatformTopology'
-import { PresentationView } from './components/features/PresentationView'
+import { PlatformView } from './components/features/PlatformView'
 import { DataQualityView } from './components/features/DataQualityView'
 import { KnowledgeChatView } from './components/features/KnowledgeChatView'
 import { StorageView } from './components/features/StorageView'
-import { HdfsView } from './components/features/HdfsView'
-import { DataGenView } from './components/features/DataGenView'
 import { ChangesView } from './components/features/ChangesView'
 import { DataFlowView } from './components/features/DataFlowView'
 import { SearchView } from './components/features/SearchView'
-import { DataSourcesView } from './components/features/DataSourcesView'
+import { DataHubView } from './components/features/DataHubView'
 import { SshTerminal } from './components/features/SshTerminal'
 import { TerminalDock } from './components/features/TerminalDock'
 import { WorkbenchPanel } from './components/features/WorkbenchPanel'
@@ -39,7 +36,7 @@ export default function App() {
   const mainScrollRef = useRef<HTMLDivElement>(null)
 
   const isPlatform = cc.mainView === 'platform'
-  const isDataSources = cc.mainView === 'datasources'
+  const isDataSources = cc.mainView === 'datasources' || cc.mainView === 'hdfs'
 
   const openApprovals = () => {
     cc.setMainView('approvals')
@@ -123,31 +120,25 @@ export default function App() {
 
               <div className={cn('flex min-h-0 flex-col', (isPlatform || isDataSources) ? 'min-h-0 flex-1 overflow-hidden' : 'min-h-0 flex-1')}>
                 {cc.mainView === 'platform' ? (
-                  <PlatformTopology
+                  <PlatformView
                     workload={cc.workload}
                     animations={cc.anims}
                     selectedNodeId={cc.selectedNodeId}
                     onNodeClick={cc.selectNode}
                     pulse={cc.genPulse}
                   />
-                ) : cc.mainView === 'datasources' ? (
-                  <DataSourcesView focusEngine={cc.dataSourceFocus} />
-                ) : cc.mainView === 'datagen' ? (
-                  <DataGenView onPulse={cc.pulseFlow} onOpenPlatform={() => cc.setMainView('platform')} />
+                ) : cc.mainView === 'datasources' || cc.mainView === 'hdfs' ? (
+                  <DataHubView focusEngine={cc.dataSourceFocus} initialTab={cc.mainView === 'hdfs' ? 'hadoop' : 'sources'} onPulse={cc.pulseFlow} />
                 ) : cc.mainView === 'changes' ? (
                   <ChangesView liveChanges={cc.changes} />
                 ) : cc.mainView === 'dataflow' ? (
                   <DataFlowView />
-                ) : cc.mainView === 'presentation' ? (
-                  <PresentationView />
                 ) : cc.mainView === 'dataquality' ? (
                   <DataQualityView />
                 ) : cc.mainView === 'knowledge' ? (
                   <KnowledgeChatView onGpuActivity={setGpuChatActive} />
                 ) : cc.mainView === 'storage' ? (
                   <StorageView />
-                ) : cc.mainView === 'hdfs' ? (
-                  <HdfsView />
                 ) : cc.mainView === 'search' ? (
                   <SearchView />
                 ) : (