feat: add fluxer upstream source and self-hosting documentation

- Clone of github.com/fluxerapp/fluxer (official upstream)
- SELF_HOSTING.md: full VM rebuild procedure, architecture overview,
  service reference, step-by-step setup, troubleshooting, seattle reference
- dev/.env.example: all env vars with secrets redacted and generation instructions
- dev/livekit.yaml: LiveKit config template with placeholder keys
- fluxer-seattle/: existing seattle deployment setup scripts

fluxer/packages/api/src/admin/services/guild/AdminGuildUpdatePropagator.tsx

@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2026 Fluxer Contributors
+ *
+ * This file is part of Fluxer.
+ *
+ * Fluxer is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Fluxer is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with Fluxer. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import type {GuildID} from '@fluxer/api/src/BrandedTypes';
+import {mapGuildToGuildResponse} from '@fluxer/api/src/guild/GuildModel';
+import type {IGuildDiscoveryRepository} from '@fluxer/api/src/guild/repositories/GuildDiscoveryRepository';
+import type {IGatewayService} from '@fluxer/api/src/infrastructure/IGatewayService';
+import {Logger} from '@fluxer/api/src/Logger';
+import type {Guild} from '@fluxer/api/src/models/Guild';
+import {getGuildSearchService} from '@fluxer/api/src/SearchFactory';
+import type {GuildDiscoveryContext} from '@fluxer/api/src/search/guild/GuildSearchSerializer';
+import {GuildFeatures} from '@fluxer/constants/src/GuildConstants';
+
+interface AdminGuildUpdatePropagatorDeps {
+	gatewayService: IGatewayService;
+	discoveryRepository: IGuildDiscoveryRepository;
+}
+
+export class AdminGuildUpdatePropagator {
+	constructor(private readonly deps: AdminGuildUpdatePropagatorDeps) {}
+
+	async dispatchGuildUpdate(guildId: GuildID, updatedGuild: Guild): Promise<void> {
+		const {gatewayService, discoveryRepository} = this.deps;
+		await gatewayService.dispatchGuild({
+			guildId,
+			event: 'GUILD_UPDATE',
+			data: mapGuildToGuildResponse(updatedGuild),
+		});
+
+		const guildSearchService = getGuildSearchService();
+		if (guildSearchService) {
+			let discoveryContext: GuildDiscoveryContext | undefined;
+			if (updatedGuild.features.has(GuildFeatures.DISCOVERABLE)) {
+				const discoveryRow = await discoveryRepository.findByGuildId(guildId);
+				if (discoveryRow) {
+					discoveryContext = {
+						description: discoveryRow.description,
+						categoryId: discoveryRow.category_type,
+					};
+				}
+			}
+			await guildSearchService.updateGuild(updatedGuild, discoveryContext).catch((error) => {
+				Logger.error({guildId, error}, 'Failed to update guild in search after admin update');
+			});
+		}
+	}
+}