Add fleet registry removal with confirm modal and agent_removed WS.

Operators can remove machines from Crucible and dashboard rosters with honest messaging that deletion is registry-only; bulk select, oath ledger entries, and Go/Vitest coverage included.

server/web/src/components/Fleet/CrucibleAgentMeta.tsx

@@ -1,13 +1,15 @@
 import { useState, useEffect } from 'react';
 import { api } from '../../api/client';
 import type { Agent } from '../../types';
+import { HelpTip } from '../HelpTip';
 
 interface Props {
   agent: Agent;
   onUpdated?: (agent: Agent) => void;
+  requestDeleteConfirm?: (req: { count: number; agentName?: string }) => Promise<boolean>;
 }
 
-export default function CrucibleAgentMeta({ agent, onUpdated }: Props) {
+export default function CrucibleAgentMeta({ agent, onUpdated, requestDeleteConfirm }: Props) {
   const [notesDraft, setNotesDraft] = useState(agent.notes || '');
   const [tagsDraft, setTagsDraft] = useState((agent.tags || []).join(', '));
   const [saving, setSaving] = useState(false);
@@ -36,7 +38,12 @@ export default function CrucibleAgentMeta({ agent, onUpdated }: Props) {
   };
 
   const deleteFromRoster = async () => {
-    if (!window.confirm('Remove this machine from the fleet roster? This cannot be undone.')) return;
+    const confirmed = requestDeleteConfirm
+      ? await requestDeleteConfirm({ count: 1, agentName: agent.name })
+      : window.confirm(
+          'Remove from fleet — does not uninstall agent on host. Remove this machine from the registry?',
+        );
+    if (!confirmed) return;
     try {
       await api.deleteAgent(agent.id);
     } catch (err) {
@@ -111,20 +118,23 @@ export default function CrucibleAgentMeta({ agent, onUpdated }: Props) {
             className="btn btn-sm"
             style={{ background: 'rgba(255,100,0,0.15)', border: '1px solid #ff8844', color: '#ffaa66' }}
             onClick={() => void uninstallAndDelete()}
-            title="Send uninstall command to agent, then remove from roster"
+            title="Send uninstall command to agent, then remove from fleet registry"
           >
-            Uninstall + Delete
+            Uninstall + Remove
           </button>
         )}
-        <button
-          type="button"
-          className="btn btn-sm"
-          style={{ background: 'rgba(255,40,40,0.15)', border: '1px solid #ff4444', color: '#ff6666' }}
-          onClick={() => void deleteFromRoster()}
-          title="Remove this machine from the fleet roster permanently"
-        >
-          Delete from Roster
-        </button>
+        <span style={{ display: 'inline-flex', alignItems: 'center', gap: '0.25rem' }}>
+          <button
+            type="button"
+            className="btn btn-sm"
+            style={{ background: 'rgba(255,40,40,0.15)', border: '1px solid #ff4444', color: '#ff6666' }}
+            onClick={() => void deleteFromRoster()}
+            title="Remove from fleet registry only — does not uninstall on host"
+          >
+            Remove from fleet
+          </button>
+          <HelpTip field="crucible_delete_roster" />
+        </span>
         {msg && <span className="form-hint">{msg}</span>}
       </div>
     </div>