fix: intended DB connection pool size not applied in default deployment

[NotYuSheng]

Problem

The default Docker deployment runs with SPRING_PROFILES_ACTIVE: dev (see docker-compose.yml). The dev profile (application-dev.yml) does not override the datasource, so the effective HikariCP pool comes from base application.yml:

spring.datasource.hikari:
  maximum-pool-size: 10
  minimum-idle: 5

The intended production sizing in application-prod.yml:

spring.datasource.hikari:
  maximum-pool-size: 20

…is never applied in the shipped deployment.

Impact

With tracepcap.analysis.max-concurrent-analyses: 3 each running batched saveAll inserts (jdbc.batch_size: 1000), plus request-serving traffic, a 10-connection pool is tight under concurrent analysis load.

Proposed fix

Make the default deployment use the intended pool size — either:

• set the pool size for the dev profile / via env var in docker-compose.yml, or
• run the prod profile in the default compose, or
• raise the base maximum-pool-size.

Confirm Postgres max_connections (default 100) comfortably covers the chosen pool size.

Acceptance

• Effective HikariCP maximum-pool-size in the default docker compose up deployment matches the intended value (verifiable via /actuator/metrics or Hikari logs).

Research context: #365