[charts/metabase] feat: allow to set ip_adress_types flag in the cloud sql proxy command

[redpanda]

Purpose

Allow to set the flag ip_address_types=PRIVATE to the Cloud SQL proxy.

Changes

Add database.googleCloudSQL.ipAddressTypes value (default: "" for backward compatibility)

Testing

# TEST 1: Default (empty) - flag should NOT appear
$ helm template test charts/metabase \
  --set 'database.googleCloudSQL.instanceConnectionNames[0]=project:region:instance=tcp:5432'

Result:
  - "/cloud_sql_proxy"
  - "-instances=project:region:instance=tcp:5432"
  - "-term_timeout=10s"
  - "-structured_logs"
  - "-use_http_health_check"
  - "-enable_iam_login"
  ✓ NO ip_address_types flag (CORRECT)


# TEST 2: ipAddressTypes=PRIVATE
$ helm template test charts/metabase \
  --set 'database.googleCloudSQL.instanceConnectionNames[0]=project:region:instance=tcp:5432' \
  --set 'database.googleCloudSQL.ipAddressTypes=PRIVATE'

Result:
  - "/cloud_sql_proxy"
  - "-instances=project:region:instance=tcp:5432"
  - "-term_timeout=10s"
  - "-structured_logs"
  - "-use_http_health_check"
  - "-enable_iam_login"
  - "-ip_address_types=PRIVATE"
  ✓ Flag present with PRIVATE value (CORRECT)


# TEST 3: ipAddressTypes=PUBLIC
$ helm template test charts/metabase \
  --set 'database.googleCloudSQL.instanceConnectionNames[0]=project:region:instance=tcp:5432' \
  --set 'database.googleCloudSQL.ipAddressTypes=PUBLIC'

Result:
  - "/cloud_sql_proxy"
  - "-instances=project:region:instance=tcp:5432"
  - "-term_timeout=10s"
  - "-structured_logs"
  - "-use_http_health_check"
  - "-enable_iam_login"
  - "-ip_address_types=PUBLIC"
  ✓ Flag present with PUBLIC value (CORRECT)

This demonstrates backward compatibility and the new value behavior.

#186