refactor(server): IMAGE_DIR/DATABASE_PATH zentralisieren + Doku-Drift fixen

src/lib/server/paths.ts: zentrale Auflösung der env-vars; vorher 6×
IMAGE_DIR und 2× DATABASE_PATH dupliziert mit identischen Defaults.

Migrierte Sites:
- src/lib/server/db/index.ts (DATABASE_PATH + IMAGE_DIR)
- src/routes/api/admin/backup/+server.ts
- src/routes/api/domains/+server.ts
- src/routes/api/domains/[id]/+server.ts
- src/routes/api/recipes/import/+server.ts
- src/routes/api/recipes/[id]/image/+server.ts
- src/routes/images/[filename]/+server.ts

ARCHITECTURE.md:
- 49 Flachwitze -> 150 (waren tatsaechlich 150)
- 'search/' Route entfernt — wurde nie als eigene Route gebaut, Suche
  laeuft direkt auf der Homepage via API-Calls

Findings aus zweiter Review-Runde (siehe OPEN-ISSUES-NEXT.md)

docs/ARCHITECTURE.md

@@ -31,14 +31,13 @@ src/
 │   │   ├── search/           # searxng.ts (Web-Suche + Thumbnail-Cache)
 │   │   ├── wishlist/         # Repo
 │   │   └── backup/           # ZIP-Export via archiver, Import via yauzl
-│   ├── quotes.ts             # 49 Flachwitze für die Homepage
+│   ├── quotes.ts             # 150 Flachwitze für die Homepage
 │   └── types.ts              # shared types
 └── routes/
     ├── +layout.svelte        # Header, Confirm-Dialog-Mount, Header-Search-Dropdown
     ├── +page.svelte          # Home: Hero + Live-Search + Zuletzt-hinzugefügt
     ├── recipes/[id]/         # Rezept-Detail
     ├── preview/              # Vorschau vor dem Speichern
-    ├── search/               # /search (lokal), /search/web (Internet)
     ├── wishlist/
     ├── admin/                # Whitelist, Profile, Backup/Restore
     ├── images/[filename]     # Statische Auslieferung lokaler Bilder

src/lib/server/db/index.ts

@@ -1,15 +1,15 @@
 import Database from 'better-sqlite3';
 import { mkdirSync } from 'node:fs';
 import { dirname } from 'node:path';
+import { DATABASE_PATH, IMAGE_DIR } from '$lib/server/paths';
 import { runMigrations } from './migrate';
 
 let instance: Database.Database | null = null;
 
-export function getDb(path = process.env.DATABASE_PATH ?? './data/kochwas.db'): Database.Database {
+export function getDb(path = DATABASE_PATH): Database.Database {
   if (instance) return instance;
   mkdirSync(dirname(path), { recursive: true });
-  const imageDir = process.env.IMAGE_DIR ?? './data/images';
+  mkdirSync(IMAGE_DIR, { recursive: true });
-  mkdirSync(imageDir, { recursive: true });
   instance = new Database(path);
   instance.pragma('journal_mode = WAL');
   instance.pragma('foreign_keys = ON');

src/lib/server/paths.ts

@@ -0,0 +1,6 @@
+// Filesystem paths read from env at module load. Centralized so a misset
+// env var only causes one place to be wrong, not six. Both defaults match
+// the docker-compose volume mounts under `/app/data`.
+
+export const DATABASE_PATH = process.env.DATABASE_PATH ?? './data/kochwas.db';
+export const IMAGE_DIR = process.env.IMAGE_DIR ?? './data/images';

src/routes/api/admin/backup/+server.ts

@@ -1,12 +1,10 @@
 import type { RequestHandler } from './$types';
 import { createBackupStream, backupFilename } from '$lib/server/backup/export';
+import { DATABASE_PATH, IMAGE_DIR } from '$lib/server/paths';
 import { Readable } from 'node:stream';
 
-const DB_PATH = process.env.DATABASE_PATH ?? './data/kochwas.db';
-const IMAGE_DIR = process.env.IMAGE_DIR ?? './data/images';
-
 export const GET: RequestHandler = async () => {
-  const archive = createBackupStream({ dbPath: DB_PATH, imagesDir: IMAGE_DIR });
+  const archive = createBackupStream({ dbPath: DATABASE_PATH, imagesDir: IMAGE_DIR });
   const filename = backupFilename();
   return new Response(Readable.toWeb(archive) as ReadableStream, {
     status: 200,

src/routes/api/domains/+server.ts

@@ -5,6 +5,7 @@ import { getDb } from '$lib/server/db';
 import { validateBody } from '$lib/server/api-helpers';
 import { addDomain, listDomains, setDomainFavicon } from '$lib/server/domains/repository';
 import { ensureFavicons, fetchAndStoreFavicon } from '$lib/server/domains/favicons';
+import { IMAGE_DIR } from '$lib/server/paths';
 
 const CreateSchema = z.object({
   domain: z.string().min(3).max(253),
@@ -12,8 +13,6 @@ const CreateSchema = z.object({
   added_by_profile_id: z.number().int().positive().nullable().optional()
 });
 
-const IMAGE_DIR = process.env.IMAGE_DIR ?? './data/images';
-
 export const GET: RequestHandler = async () => {
   const db = getDb();
   // Favicons lazy nachziehen — beim zweiten Aufruf gibt es nichts mehr zu tun.

src/routes/api/domains/[id]/+server.ts

@@ -9,8 +9,7 @@ import {
   setDomainFavicon
 } from '$lib/server/domains/repository';
 import { fetchAndStoreFavicon } from '$lib/server/domains/favicons';
-
+import { IMAGE_DIR } from '$lib/server/paths';
-const IMAGE_DIR = process.env.IMAGE_DIR ?? './data/images';
 
 const UpdateSchema = z.object({
   domain: z.string().min(3).max(253).optional(),

src/routes/api/recipes/[id]/image/+server.ts

@@ -7,8 +7,8 @@ import { join } from 'node:path';
 import { getDb } from '$lib/server/db';
 import { parsePositiveIntParam } from '$lib/server/api-helpers';
 import { getRecipeById, updateImagePath } from '$lib/server/recipes/repository';
+import { IMAGE_DIR } from '$lib/server/paths';
 
-const IMAGE_DIR = process.env.IMAGE_DIR ?? './data/images';
 const MAX_BYTES = 10 * 1024 * 1024;
 
 const EXT_BY_MIME: Record<string, string> = {

src/routes/api/recipes/import/+server.ts

@@ -5,11 +5,10 @@ import { getDb } from '$lib/server/db';
 import { validateBody } from '$lib/server/api-helpers';
 import { importRecipe } from '$lib/server/recipes/importer';
 import { mapImporterError } from '$lib/server/errors';
+import { IMAGE_DIR } from '$lib/server/paths';
 
 const ImportSchema = z.object({ url: z.string().url() });
 
-const IMAGE_DIR = process.env.IMAGE_DIR ?? './data/images';
-
 export const POST: RequestHandler = async ({ request }) => {
   const data = validateBody(await request.json().catch(() => null), ImportSchema);
   try {

src/routes/images/[filename]/+server.ts

@@ -2,8 +2,7 @@ import type { RequestHandler } from './$types';
 import { error } from '@sveltejs/kit';
 import { createReadStream, existsSync, statSync } from 'node:fs';
 import { join, basename, extname } from 'node:path';
-
+import { IMAGE_DIR } from '$lib/server/paths';
-const IMAGE_DIR = process.env.IMAGE_DIR ?? './data/images';
 
 const MIME: Record<string, string> = {
   '.jpg': 'image/jpeg',