fix(helm): address CodeRabbit review findings

NOTES.txt:
- Detect ingress scheme dynamically (http/https based on .Values.ingress.tls)
- Include first path in ingress URL output
- Use .Values.service.port in port-forward example instead of hardcoded 80
- Add -n {{ .Release.Namespace }} to all kubectl commands

postiz-config.yaml:
- Merge temporal enabled/external branches: external address now also emits
  TEMPORAL_NAMESPACE and TEMPORAL_TLS, not just TEMPORAL_ADDRESS

temporal-init-job.yaml:
- Use .Values.temporal.postgresql.seeds as PGHOST source (with fallback to
  bitnami sub-chart service name) so init job and runtime use the same host
- Switch to quoted heredoc (<<-'SQL') + psql --set to pass credentials as
  psql variables, preventing shell expansion from breaking on special chars

temporal-secret.yaml:
- Add required validation: temporal.postgresql.password must be set explicitly
  when temporal.enabled=true

values.yaml:
- Remove hardcoded default passwords (postgresPassword, temporal.postgresql.password)
  replaced with empty strings to avoid predictable default credentials

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

charts/postiz/templates/postiz-config.yaml

@@ -8,10 +8,8 @@ data:
   {{- range $key, $value := .Values.env }}
   {{ $key }}: {{ $value | quote }}
   {{- end }}
-  {{- if .Values.temporal.enabled }}
+  {{- if or .Values.temporal.enabled .Values.temporal.address }}
   TEMPORAL_ADDRESS: {{ default (printf "%s-temporal:7233" (include "postiz.fullname" .)) .Values.temporal.address | quote }}
   TEMPORAL_NAMESPACE: {{ .Values.temporal.namespace | default "default" | quote }}
   TEMPORAL_TLS: {{ .Values.temporal.tls | toString | quote }}
-  {{- else if .Values.temporal.address }}
-  TEMPORAL_ADDRESS: {{ .Values.temporal.address | quote }}
   {{- end }}