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/rate_limit/src/RateLimitService.tsx

@@ -0,0 +1,114 @@
+/*
+ * 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 {ICacheService} from '@fluxer/rate_limit/src/ICacheService';
+import {InMemoryCacheService} from '@fluxer/rate_limit/src/InMemoryCacheService';
+import type {
+	BucketConfig,
+	IRateLimitService,
+	RateLimitConfig,
+	RateLimitResult,
+} from '@fluxer/rate_limit/src/IRateLimitService';
+import {GcraRateLimiter} from '@fluxer/rate_limit/src/internal/GcraRateLimiter';
+import {RateLimitKeyFactory} from '@fluxer/rate_limit/src/internal/RateLimitKeyFactory';
+import {assertPositiveFiniteNumber} from '@fluxer/rate_limit/src/internal/RateLimitValidation';
+
+export interface RateLimitServiceOptions {
+	globalWindowMs?: number;
+	getCurrentTimeMs?: () => number;
+}
+
+export class RateLimitService implements IRateLimitService {
+	private static readonly DEFAULT_GLOBAL_WINDOW_MS = 1000;
+	private readonly gcraRateLimiter: GcraRateLimiter;
+	private readonly keyFactory: RateLimitKeyFactory;
+	private readonly globalWindowMs: number;
+
+	constructor(cacheService: ICacheService, options: RateLimitServiceOptions = {}) {
+		this.gcraRateLimiter = new GcraRateLimiter(cacheService, options.getCurrentTimeMs);
+		this.keyFactory = new RateLimitKeyFactory();
+		this.globalWindowMs = options.globalWindowMs ?? RateLimitService.DEFAULT_GLOBAL_WINDOW_MS;
+		assertPositiveFiniteNumber(this.globalWindowMs, 'globalWindowMs');
+	}
+
+	async checkLimit(config: RateLimitConfig): Promise<RateLimitResult> {
+		const key = this.keyFactory.getIdentifierKey(config.identifier);
+		return this.gcraRateLimiter.checkLimit(key, {
+			limit: config.maxAttempts,
+			windowMs: config.windowMs,
+		});
+	}
+
+	async checkBucketLimit(bucket: string, config: BucketConfig): Promise<RateLimitResult> {
+		const key = this.keyFactory.getBucketKey(bucket);
+		return this.gcraRateLimiter.checkLimit(key, {
+			limit: config.limit,
+			windowMs: config.windowMs,
+		});
+	}
+
+	async checkGlobalLimit(identifier: string, limit: number): Promise<RateLimitResult> {
+		const key = this.keyFactory.getGlobalKey(identifier);
+		return this.gcraRateLimiter.checkLimit(
+			key,
+			{
+				limit,
+				windowMs: this.globalWindowMs,
+			},
+			{global: true},
+		);
+	}
+
+	async resetLimit(identifier: string): Promise<void> {
+		const key = this.keyFactory.getIdentifierKey(identifier);
+		await this.gcraRateLimiter.resetLimit(key);
+	}
+
+	async getRemainingAttempts(identifier: string, _windowMs: number): Promise<number> {
+		const key = this.keyFactory.getIdentifierKey(identifier);
+		return this.gcraRateLimiter.getRemainingAttempts(key);
+	}
+
+	async getResetTime(identifier: string, _windowMs: number): Promise<Date> {
+		const key = this.keyFactory.getIdentifierKey(identifier);
+		return this.gcraRateLimiter.getResetTime(key);
+	}
+}
+
+export function createRateLimitService(
+	cacheService: ICacheService | null,
+	options: RateLimitServiceOptions = {},
+): RateLimitService | null {
+	if (!cacheService) {
+		return null;
+	}
+	return new RateLimitService(cacheService, options);
+}
+
+export function createInMemoryRateLimitService(
+	enabled: boolean,
+	options: RateLimitServiceOptions = {},
+): RateLimitService | null {
+	if (!enabled) {
+		return null;
+	}
+
+	const cacheService = new InMemoryCacheService();
+	return createRateLimitService(cacheService, options);
+}