feat(m0): bootstrap repo, design system, compose stack

- Repo scaffolding: .gitignore, .env.example, Makefile, docker-compose.yml,
  README.md, CHANGELOG.md, pre-commit config.
- Three-service stack: api (Flask 3), db (postgres:16-alpine), front (nginx
  serving the Vite bundle). Named volumes metamorph_db + metamorph_evidence.
- Backend skeleton: Flask app factory, JSON structured logging on stdout,
  GET /api/v1/health, multi-stage Dockerfile, pyproject.toml driven by uv,
  Pydantic Settings with secret guard rails (refuses to boot in non-dev with
  placeholders), APP_ENV gating.
- Frontend skeleton: Vite + React 18 + TypeScript strict + TailwindCSS, RTOps
  design tokens from tasks/design.md, self-hosted JetBrains Mono / IBM Plex
  Sans via @fontsource, base UI primitives (Card/Tag/SectionHeader/FlowNode/
  Button), home page wired to /api/v1/health.
- Engine-agnostic Makefile: auto-detects docker or podman, picks the matching
  compose driver. Targets: up/down/build/rebuild/dev/lint/fmt/test/migrate/
  seed-mitre/print-install-token/e2e/inspect-health.
- Playwright suite: e2e/tests/m0-smoke.spec.ts (8 tests) + HTML + JUnit
  reports + traces on retry.
- Docs: tasks/spec.md (finalized after Q&A), tasks/design.md, tasks/todo.md
  (14 milestones), tasks/testing-m0.md, tasks/lessons.md.

DoD: make up + make health + make e2e all pass on podman 5.x (Fedora) and
docker. TLS terminated by external reverse proxy (spec §6 NF-network).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

backend/app/core/logging.py

@@ -0,0 +1,34 @@
+"""JSON structured logging on stdout."""
+
+from __future__ import annotations
+
+import logging
+import sys
+
+from pythonjsonlogger import jsonlogger
+
+
+def configure_logging(level: str = "INFO") -> None:
+    """Replace the root handler with a single JSON stdout handler.
+
+    Fields emitted: ts, level, name, msg, plus any extras passed via `logger.X(..., extra={...})`.
+    """
+    root = logging.getLogger()
+    root.setLevel(level.upper())
+
+    # Drop any pre-existing handlers (uvicorn/gunicorn add their own).
+    for h in list(root.handlers):
+        root.removeHandler(h)
+
+    handler = logging.StreamHandler(sys.stdout)
+    formatter = jsonlogger.JsonFormatter(
+        fmt="%(asctime)s %(levelname)s %(name)s %(message)s",
+        rename_fields={"asctime": "ts", "levelname": "level", "name": "logger"},
+        json_ensure_ascii=False,
+    )
+    handler.setFormatter(formatter)
+    root.addHandler(handler)
+
+    # Tame the noisy third parties unless explicitly debugging.
+    if level.upper() != "DEBUG":
+        logging.getLogger("werkzeug").setLevel(logging.WARNING)