fix(review-2): medium/low + docs — config validation, hygiene, doc sync

- compression_concurrency wired to boot config (state.rs) and removed as a
  dead admin control.
- patch_config gains per-key integer/range validation so numerically-valid-but-
  nonsensical values (-1/NaN/3.5) are rejected instead of silently reverting to
  default at read time.
- clearAuth now also clears the display name (shared-device residual).
- e2e/Caddyfile.test mirrors prod security headers + the SSE encode-exclusion so
  the test stack is representative and can catch header regressions.
- .gitignore: ignore root-level Playwright artifacts (test-results/, report).
- docs: USER_JOURNEYS §10 and SECURITY-BACKLOG updated to match the implemented
  read-only-ban behavior and the export-path fix.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.gitignore

@@ -22,6 +22,9 @@ e2e/playwright-report/
 e2e/test-results/
 e2e/.cache/
 e2e/.env.test
+# Playwright artifacts when run from the repo root instead of e2e/
+/test-results/
+/playwright-report/
 
 # OS
 .DS_Store

backend/src/handlers/admin.rs

@@ -121,15 +121,18 @@ pub async fn patch_config(
     // Numeric keys validated as f64; boolean keys validated as truthy strings; the
     // privacy note is free text. Splitting these explicitly is verbose but makes the
     // failure mode for typos obvious (`Unbekannter Schlüssel: ...`).
-    const NUMERIC_KEYS: &[&str] = &[
-        "max_image_size_mb",
-        "max_video_size_mb",
-        "upload_rate_per_hour",
-        "feed_rate_per_min",
-        "export_rate_per_day",
-        "quota_tolerance",
-        "estimated_guest_count",
-        "compression_concurrency",
+    // (key, integer_only, min, max). Ranges reject values that `parse::<f64>` would
+    // accept but that silently revert to the hardcoded default at read time
+    // (get_usize/get_i64 can't parse negatives/NaN/fractionals). `compression_concurrency`
+    // is intentionally absent — it's read once at boot, so a live edit was a no-op.
+    const NUMERIC_SPECS: &[(&str, bool, f64, f64)] = &[
+        ("max_image_size_mb", true, 1.0, 1024.0),
+        ("max_video_size_mb", true, 1.0, 10240.0),
+        ("upload_rate_per_hour", true, 1.0, 100_000.0),
+        ("feed_rate_per_min", true, 1.0, 100_000.0),
+        ("export_rate_per_day", true, 1.0, 100_000.0),
+        ("quota_tolerance", false, 0.0, 1.0),
+        ("estimated_guest_count", true, 1.0, 1_000_000.0),
     ];
     const BOOL_KEYS: &[&str] = &[
         "rate_limits_enabled",
@@ -150,10 +153,26 @@ pub async fn patch_config(
     // update behind — validation must fully precede any write.
     for (key, value) in &body {
         let key_str = key.as_str();
-        if NUMERIC_KEYS.contains(&key_str) {
-            if value.parse::<f64>().is_err() {
+        if let Some(&(_, integer_only, min, max)) =
+            NUMERIC_SPECS.iter().find(|(k, ..)| *k == key_str)
+        {
+            let n = value.trim().parse::<f64>().ok().filter(|n| n.is_finite());
+            let n = match n {
+                Some(n) => n,
+                None => {
+                    return Err(AppError::BadRequest(format!(
+                        "Ungültiger Wert für {key}: muss eine Zahl sein."
+                    )))
+                }
+            };
+            if integer_only && n.fract() != 0.0 {
                 return Err(AppError::BadRequest(format!(
-                    "Ungültiger Wert für {key}: muss eine Zahl sein."
+                    "Ungültiger Wert für {key}: muss eine ganze Zahl sein."
+                )));
+            }
+            if n < min || n > max {
+                return Err(AppError::BadRequest(format!(
+                    "Wert für {key} liegt außerhalb des zulässigen Bereichs ({min}–{max})."
                 )));
             }
         } else if BOOL_KEYS.contains(&key_str) {
@@ -282,7 +301,7 @@ pub async fn download_zip(
         ));
     }
 
-    let path = state.config.media_path.join("exports").join("Gallery.zip");
+    let path = state.config.export_path.join("Gallery.zip");
     if !path.exists() {
         return Err(AppError::NotFound("Exportdatei nicht gefunden.".into()));
     }
@@ -308,7 +327,7 @@ pub async fn download_html(
         ));
     }
 
-    let path = state.config.media_path.join("exports").join("Memories.zip");
+    let path = state.config.export_path.join("Memories.zip");
     if !path.exists() {
         return Err(AppError::NotFound("Exportdatei nicht gefunden.".into()));
     }

backend/src/state.rs

@@ -36,8 +36,12 @@ pub struct AppState {
 impl AppState {
     pub fn new(pool: PgPool, config: AppConfig) -> Self {
         let (sse_tx, _) = broadcast::channel(256);
-        let compression =
-            CompressionWorker::new(pool.clone(), config.media_path.clone(), 2, sse_tx.clone());
+        let compression = CompressionWorker::new(
+            pool.clone(),
+            config.media_path.clone(),
+            config.compression_concurrency,
+            sse_tx.clone(),
+        );
         Self {
             pool,
             config,

docs/SECURITY-BACKLOG.md

@@ -64,8 +64,11 @@ decompression-bomb cap (`image::Limits` 12000×12000 / 256 MiB) lives in
   (not just the exact dev sentinel) and enforces `len ≥ 32` unconditionally in prod.
 - **Unspoofable client IP in the rate limiter** — `client_ip` now takes the right-most
   `X-Forwarded-For` entry (the hop Caddy appends), so a client-supplied left-most value is ignored.
-- **Live role/ban re-check** — the auth extractor re-reads the user row and trusts the DB role and
-  `is_banned` flag rather than the JWT claim, revoking demoted/banned sessions immediately.
+- **Live role/ban re-check** — the auth extractor re-reads the user row and trusts the DB `role`
+  and `is_banned` flag rather than the JWT claim, so a demote/ban takes effect immediately (no
+  30-day token window). Bans are enforced on write handlers + the host/admin extractors, preserving
+  the documented read-only access for banned guests (USER_JOURNEYS §10); demoted hosts lose host
+  powers at once.
 - **Container healthchecks** — `app` and `frontend` now have healthchecks and Caddy waits on
   `service_healthy`.
 - **Event-scoped `ban_user`** — the ban UPDATE is now scoped by `event_id` like its siblings.

docs/USER_JOURNEYS.md

@@ -147,12 +147,18 @@ the Host can clean up later).
 
 ## 10. Banned-guest experience
 
-1. The banned user's next authenticated request returns HTTP 403 with a clear message
-   ("Du bist gesperrt.").
-2. They can still browse the read-only feed (and download the export once it's released).
-3. They cannot upload, like, or comment.
-4. If `hide_uploads` was set on the ban, their existing uploads are filtered out of the
-   feed for everyone (the `v_feed` view already enforces this).
+1. The ban takes effect immediately on the banned user's existing session — the auth
+   layer re-reads the live `is_banned` flag on every request rather than trusting the
+   JWT, so there's no 30-day token-lifetime window.
+2. Their next authenticated *write* request returns HTTP 403 with a clear message
+   ("Du bist gesperrt."). Ban enforcement lives on the write handlers and the
+   host/admin extractors, not the base auth extractor.
+3. They can still browse the read-only feed (and download the export once it's released).
+4. They cannot upload, like, or comment; a banned host also loses all host/admin
+   actions (including unbanning themselves).
+5. If `hide_uploads` was set on the ban, their existing uploads are filtered out of the
+   feed for everyone (`v_feed` enforces this), and a live `user-hidden` SSE event evicts
+   their cards from every open feed + the diashow without a reload.
 
 ## 11. Admin — instance configuration
 

e2e/Caddyfile.test

@@ -4,7 +4,17 @@
 # of HTTPS/Let's Encrypt.
 
 :3101 {
-    encode zstd gzip
+    # Mirror prod: exclude the SSE stream from compression so buffering doesn't
+    # delay real-time events (and so the test stack exercises the real behavior).
+    @compressible not path /api/v1/stream
+    encode @compressible zstd gzip
+
+    # Mirror prod's security headers (minus HSTS, which is HTTPS-only).
+    header {
+        X-Content-Type-Options "nosniff"
+        X-Frame-Options "DENY"
+        Referrer-Policy "strict-origin-when-cross-origin"
+    }
 
     reverse_proxy /api/* app:3000
     reverse_proxy /media/* app:3000

e2e/helpers/seed.ts

@@ -3,11 +3,26 @@
  * flow. Centralising the API contract (routes, field names, expected statuses)
  * means an API change is a one-file edit, not a 7-file hunt.
  */
-import { uploadRaw, JPEG_MAGIC } from './upload-client';
+import { readFileSync } from 'node:fs';
+import { join } from 'node:path';
+import { uploadRaw } from './upload-client';
 import { db } from '../fixtures/db';
 
 const BASE = process.env.E2E_FRONTEND_URL ?? 'http://localhost:3101';
 
+// A real, decodable JPEG. Magic-bytes-only fakes now get auto-cleaned by the
+// backend when compression fails (a failed transcode refunds quota + deletes the
+// row), which would delete the seeded upload out from under the test. Read lazily
+// at call time (cwd is the e2e dir at runtime, like the gallery-path spec) so test
+// collection can't trip on a module-load read.
+let sampleJpg: Buffer | null = null;
+function sampleImage(): Buffer {
+  if (!sampleJpg) {
+    sampleJpg = readFileSync(join(process.cwd(), 'fixtures', 'media', 'sample.jpg'));
+  }
+  return sampleJpg;
+}
+
 export type SeedUploadOptions = {
   caption?: string;
   /** Mark compression done so the card is fully rendered in the feed. Default true. */
@@ -16,9 +31,7 @@ export type SeedUploadOptions = {
 
 /** Seed a real, accepted upload owned by `jwt` and return its id. */
 export async function seedUpload(jwt: string, opts: SeedUploadOptions = {}): Promise<string> {
-  const body = new Uint8Array(1024);
-  body.set(JPEG_MAGIC, 0);
-  const res = await uploadRaw(jwt, body, {
+  const res = await uploadRaw(jwt, sampleImage(), {
     filename: 'a.jpg',
     contentType: 'image/jpeg',
     caption: opts.caption,

frontend/src/lib/auth.ts

@@ -83,6 +83,9 @@ export function clearAuth(): void {
 	if (!browser) return;
 	localStorage.removeItem(TOKEN_KEY);
 	localStorage.removeItem(USER_ID_KEY);
+	// Clear the display name too — on a shared device the next user shouldn't see
+	// the previous guest's name pre-filled on /join.
+	localStorage.removeItem(DISPLAY_NAME_KEY);
 	// PIN is intentionally kept so the user can recover
 	isAuthenticated.set(false);
 	// Hooks fire in registration order. Keep them dependency-free of each other —