feat(infra): add Bitwarden Secrets Manager injection for container secrets

Adds a bws-CLI build stage to the Dockerfile and a docker-entrypoint.sh
that runs `bws run -- node server.js` when BWS_ACCESS_TOKEN is set,
falling back to a plain `node server.js` start when it's not. Lets AWS
Route 53 credentials (and any future BWS-managed secret) reach the
container without ever being written to the committed .env file.

Fixed during phase 24 verification:
- The bws CLI config only set state_dir; bws 2.x requires server_base
  (or server_identity) even for the default Bitwarden cloud instance,
  which crash-looped the container on every start. Added
  server_base = "https://vault.bitwarden.com".
- docker-compose.yml's app.environment block re-declared
  BWS_ACCESS_TOKEN/BWS_PROJECT_ID as ${VAR:-} substitutions, which
  resolve against the root .env (not .env.local) and silently
  overrode the real token with an empty string. Removed the redundant
  re-declaration — env_file: .env.local already injects them.

Verified live: pulse-app rebuilt and restarted with both fixes,
AWS credentials confirmed reaching the Node process via BWS injection.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

docker-entrypoint.sh

@@ -0,0 +1,10 @@
+#!/bin/sh
+set -e
+
+if [ -n "${BWS_ACCESS_TOKEN:-}" ]; then
+  echo "Loading secrets from Bitwarden Secrets Manager..."
+  exec bws run ${BWS_PROJECT_ID:+--project-id "${BWS_PROJECT_ID}"} -- node server.js
+fi
+
+echo "BWS_ACCESS_TOKEN not set; starting without Bitwarden secrets."
+exec node server.js