refactor: rename package fabledassistant -> scribe (code-only)

Renames src/fabledassistant -> src/scribe and all imports, plus the
default DB name and DB user/password (fabled -> scribe) in config +
compose. 952 refs / 154 files. Reverses the old 'internal name stays
fabledassistant' convention.

Code-only: live databases are still physically named 'fabledassistant'.
Deployed environments must set POSTGRES_DB / POSTGRES_USER (or rename the
DB) since the defaults now resolve to 'scribe'. Repo (FabledScribe), git
host (fabledsword), MCP (fabled-git) and the image name (fabledscribe)
are intentionally unchanged.

ruff check src/ clean locally; CI (typecheck + pytest) is the gate.

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

docker-compose.quickstart.yml

@@ -18,7 +18,7 @@ services:
     ports:
       - "5000:5000"
     environment:
-      DATABASE_URL: "postgresql+asyncpg://fabled:fabled@db:5432/fabledassistant"
+      DATABASE_URL: "postgresql+asyncpg://scribe:scribe@db:5432/scribe"
       SECRET_KEY: "${SECRET_KEY:-change-me-in-production}"
       LOG_LEVEL: "${LOG_LEVEL:-INFO}"
     volumes:
@@ -40,13 +40,13 @@ services:
     volumes:
       - pgdata:/var/lib/postgresql/data
     environment:
-      POSTGRES_USER: fabled
-      POSTGRES_PASSWORD: fabled
-      POSTGRES_DB: fabledassistant
+      POSTGRES_USER: scribe
+      POSTGRES_PASSWORD: scribe
+      POSTGRES_DB: scribe
     # Lenient by design: a transient host exec/healthcheck stall must never
     # escalate to killing the DB. Health here only gates app startup order.
     healthcheck:
-      test: ["CMD-SHELL", "pg_isready -U fabled"]
+      test: ["CMD-SHELL", "pg_isready -U scribe"]
       interval: 30s
       timeout: 10s
       retries: 10