Improve portable launch, forge persistence, and operator auth UX.

Persist build extra_files for Build Manager history, print dashboard login on every start, add libp2p for Mesh P2P forge, defer WebSocket until login, and split devrun.bat from LAUNCH.bat with USB deck auto-detection.

server/web/src/pages/BuilderPage.tsx

@@ -19,7 +19,7 @@ import {
   type ForgeDeliverable,
 } from '../help/forgeFormNormalize';
 import { ForgeFieldBadge, ForgeLockedHint, ForgeSectionHeader } from '../components/Forge/ForgeFieldHints';
-import { buildRequestFromRecord } from '../help/buildManager';
+import { blueprintDiff, buildRequestFromRecord } from '../help/buildManager';
 import DownloadButton from '../components/DownloadButton';
 import { useForge } from '../context/ForgeContext';
 import {
@@ -272,6 +272,7 @@ export default function BuilderPage() {
     try {
       const data = await api.getBlueprint(name);
       setCompareBlueprint(data as Record<string, unknown>);
+      setBlueprintName(name);
       // Merge loaded data into form, preserving any fields not in the blueprint
       setForm((prev) => (prev ? { ...prev, ...data } : prev));
       setShowBlueprints(false);
@@ -341,7 +342,9 @@ export default function BuilderPage() {
     const reader = new FileReader();
     reader.onload = (evt) => {
       try {
-        const data = JSON.parse(evt.target?.result as string);
+        const data = JSON.parse(evt.target?.result as string) as Record<string, unknown>;
+        setCompareBlueprint(data);
+        setBlueprintName(file.name);
         setForm((prev) => (prev ? { ...prev, ...data } : prev));
         setBlueprintMsg(`✅ Blueprint loaded from "${file.name}"`);
         setTimeout(() => setBlueprintMsg(''), 3000);
@@ -594,6 +597,10 @@ export default function BuilderPage() {
   );
   const canForge = form ? !preflightHasErrors(preflightChecks) : false;
   const errorCount = preflightChecks.filter((c) => c.level === 'error').length;
+  const blueprintChanges = useMemo(() => {
+    if (!compareBlueprint || !form) return [];
+    return blueprintDiff(compareBlueprint, form as unknown as Record<string, unknown>);
+  }, [compareBlueprint, form]);
   const fusionIsExe = fusionPayloadKind(fusionPrepFile) === 'exe';
   const fusionMediaMode = form?.fusion_media_mode || 'paired';
 
@@ -754,6 +761,44 @@ export default function BuilderPage() {
         </div>
       )}
 
+      {compareBlueprint && blueprintChanges.length > 0 && (
+        <div className="card" style={{ marginBottom: '16px' }}>
+          <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', marginBottom: '8px' }}>
+            <h3 style={{ margin: 0, fontSize: '1rem' }}>
+              Blueprint diff — {blueprintName || 'loaded blueprint'}
+            </h3>
+            <button
+              type="button"
+              className="btn btn-outline btn-sm"
+              onClick={() => {
+                setCompareBlueprint(null);
+                setBlueprintName('');
+              }}
+            >
+              Dismiss
+            </button>
+          </div>
+          <p className="form-hint" style={{ marginTop: 0 }}>
+            Fields that differ from the loaded blueprint (your previous form values were kept where they conflict).
+          </p>
+          <ul className="blueprint-diff-list" style={{ margin: 0, paddingLeft: '1.25rem', fontSize: '0.85rem' }}>
+            {blueprintChanges.map((row) => (
+              <li key={row.key}>
+                <code>{row.key}</code>
+                {' — '}
+                {row.kind === 'added' && <span>kept from form</span>}
+                {row.kind === 'removed' && <span>not in current form</span>}
+                {row.kind === 'changed' && (
+                  <span>
+                    blueprint → current
+                  </span>
+                )}
+              </li>
+            ))}
+          </ul>
+        </div>
+      )}
+
       {/* Blueprint picker panel */}
       {showBlueprints && (
         <div className="card" style={{ marginBottom: '16px' }}>
@@ -2022,6 +2067,19 @@ export default function BuilderPage() {
                   ↓ Download
                 </DownloadButton>
               )}
+              {lastBuild.build_id &&
+                lastBuild.extra_files?.map((f) =>
+                  f.file_name ? (
+                    <DownloadButton
+                      key={f.file_name}
+                      apiPath={api.buildArtifactUrl(lastBuild.build_id!, f.file_name)}
+                      filename={f.file_name}
+                      className="btn btn-outline btn-sm"
+                    >
+                      ↓ {f.file_name}
+                    </DownloadButton>
+                  ) : null
+                )}
               <button
                 type="button"
                 className="btn btn-outline btn-sm"