fix: strip null bytes from copied files, add missing package-lock.json

Several source files contained trailing NULL bytes introduced by the
cross-filesystem copy (Windows CIFS mount → Linux). This caused
export-filenames.ts and others to be detected as binary, breaking
the build.

Affected files cleaned: export-filenames.ts, zip-export-formats.ts,
export.ts, http-export-card.tsx, zip-export.spec.ts, ui-store.ts.

Also adds the missing package-lock.json update for the fflate
dependency added in package.json.

Author: stephanbuettig

package-lock.json

@@ -241,4 +241,3 @@ export class HttpExportCard extends React.Component<ExportCardProps> {
         this.props.uiStore!.exportSnippetFormat = optionKey;
     }
 };
-

src/components/view/http/http-export-card.tsx

@@ -598,4 +598,3 @@ export class UiStore {
     }
 
 }
-

src/model/ui/export.ts

@@ -197,4 +197,3 @@ export function sanitizeFormatIds(ids: Iterable<string>): string[] {
     }
     return out;
 }
-

src/model/ui/ui-store.ts

@@ -338,4 +338,3 @@ describe('ZIP export worker round-trip', function () {
         expect(res.snippetErrorCount).to.equal(0);
     });
 });
-