Fix proton-bridge default port wiring for Kubernetes

[mgarratt]

Summary

• set proton-bridge chart default container ports to 1026/1144 to avoid colliding with bridge internal listener ports 1025/1143
• add a template guard that fails fast if bridge and container ports are set equal while using a local bridge host (127.0.0.1, localhost, ::1)
• update README defaults and bump chart version to 0.1.7

Why

Current chart defaults set both PROTON_BRIDGE_* and CONTAINER_* to the same values, which causes runtime bind failures (address already in use) in Kubernetes deployments.

Validation

• helm lint charts/proton-bridge passes locally
• verified rendered secret/env values now keep bridge and container ports distinct by default