docs: consolidate changelog into 0.14.0 + refresh README

Cut [0.14.0] consolidating SLM live monitoring, the FTP night-report
pipeline (was missing from the changelog entirely), the client portal,
and portal auth Phase 1 under one entry. Bump VERSION + README to 0.14.0
and add the sound-monitoring / night-report / client-portal features to
the README.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

backend/main.py

@@ -30,7 +30,7 @@ Base.metadata.create_all(bind=engine)
 ENVIRONMENT = os.getenv("ENVIRONMENT", "production")
 
 # Initialize FastAPI app
-VERSION = "0.13.3"
+VERSION = "0.14.0"
 if ENVIRONMENT == "development":
     _build = os.getenv("BUILD_NUMBER", "0")
     if _build and _build != "0":