Add Docker Compose for Postgres setup and update configs

Added a Docker Compose file for setting up a Postgres container easily. Updated `local_db.md` with a corrected `docker run` command and adjusted database configuration in `application-local.yaml` to match the new setup.

apps/dolly-backend/src/main/resources/application-local.yaml

@@ -11,12 +11,9 @@ spring:
       generic:
         enabled: false
   datasource:
-    url: jdbc:postgresql://localhost:5432/dolly-test
-    username: postgres
-    hikari:
-      maximum-pool-size: 3
-      minimum-idle: 1
+    url: jdbc:postgresql://localhost:5432/postgres
     driver-class-name: org.postgresql.Driver
+    username: postgres
 
 management:
   endpoints:

docs/compose.yaml

@@ -0,0 +1,10 @@
+services:
+  postgres:
+    container_name: postgres
+    image: postgres:latest
+    environment:
+      - POSTGRES_DB=postgres
+      - POSTGRES_HOST_AUTH_METHOD=trust
+    ports:
+      - "5432:5432"
+    restart: always

docs/local_db.md

@@ -47,7 +47,7 @@ Legg merke til at vi bruker `--exclude-table` i dette eksempelet. I denne databa
 **Dette gjøres bare én gang.** Vi lager oss en container kalt `postgres`, der auth er slått av fra din Docker host. Default-brukeren `postgres` vil stå som eier av alle tabeller.
 
 ~~~
-> docker run --name postgres -e POSTGRES_HOST_AUTH_METHOD=trust -p 5432:5432 postgres
+> docker run --name postgres -e POSTGRES_HOST_AUTH_METHOD=trust -p 5432:5432 postgres -c
 ~~~
 
 Her kjøres containeren uten `--detach`, slik at vi kan følge med på logger i tilfelle feil under import, men det er valgfritt.