docs: README badges + screenshot section (#28)

Author: constk

README.md

@@ -1,5 +1,13 @@
 # harness-python-react
 
+[![CI](https://github.com/constk/harness-python-react/actions/workflows/ci.yml/badge.svg?branch=develop)](https://github.com/constk/harness-python-react/actions/workflows/ci.yml)
+[![Security](https://github.com/constk/harness-python-react/actions/workflows/security.yml/badge.svg?branch=develop)](https://github.com/constk/harness-python-react/actions/workflows/security.yml)
+[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](LICENSE)
+[![Python 3.14](https://img.shields.io/badge/python-3.14-blue.svg)](https://www.python.org/)
+[![Node 24 LTS](https://img.shields.io/badge/node-24%20LTS-43853d.svg)](https://nodejs.org/)
+[![React 19.2](https://img.shields.io/badge/react-19.2-61dafb.svg)](https://react.dev/)
+[![Coverage 98%](https://img.shields.io/badge/coverage-98%25-brightgreen.svg)](docs/HARNESS.md)
+
 > A production-quality coding harness for Python (FastAPI) + Vite/React/TypeScript projects. Designed for LLM-driven development: every gate — lint, types, architecture, security, eval — is enforced mechanically so code quality stays consistent across many human and AI contributors.
 
 ## What ships
@@ -27,6 +35,61 @@ docker compose up   # backend :8000, frontend :5173, Jaeger :16686
 
 The pre-push gate is `just check` (= ruff + mypy + import-linter + pytest). For frontend changes add `just frontend-check`.
 
+## Screenshots
+
+### `just check` — local pre-push gate
+
+What every contributor sees before pushing:
+
+```text
+$ uv run --frozen ruff check .
+All checks passed!
+
+$ uv run --frozen ruff format --check .
+37 files already formatted
+
+$ uv run --frozen mypy --strict src/ tests/
+Success: no issues found in 31 source files
+
+$ uv run --frozen lint-imports
+Analyzed 24 files, 15 dependencies.
+
+src layers flow one-way (api/eval -> agent -> tools -> data -> observability ->
+models) KEPT
+src.models depends on nothing in src/ KEPT
+
+Contracts: 2 kept, 0 broken.
+
+$ uv run --frozen pytest tests/ --cov=src --cov-report=term
+============================= 40 passed in 0.75s ==============================
+TOTAL                             221      3    99%
+Required test coverage of 75.0% reached. Total coverage: 98.64%
+```
+
+### CI on a sample PR
+
+Eight backend + two frontend + four security jobs all green on every PR:
+
+![CI status](docs/images/ci-green.png)
+
+> **Capture:** open <https://github.com/constk/harness-python-react/actions/workflows/ci.yml>, click any green run on `develop`, screenshot the job-list panel. Save as `docs/images/ci-green.png`.
+
+### Hello page (`docker compose up`)
+
+The scaffold's React page hits `/api/v1/health` on load and renders the version + status badge:
+
+![Hello page](docs/images/hello-page.png)
+
+> **Capture:** `docker compose up`, open <http://localhost:5173>, screenshot.
+
+### Jaeger trace for `/api/v1/health`
+
+OTel auto-instrumentation produces one span per request, exported via OTLP gRPC to the local Jaeger:
+
+![Jaeger trace](docs/images/jaeger-trace.png)
+
+> **Capture:** with the stack running, hit `/api/v1/health` once, then open <http://localhost:16686>, select service `harness-python-react`, click the most recent trace, screenshot the span timeline.
+
 ## Why a harness
 
 The differentiator isn't the scaffold — it's that every layer of the pipeline catches a different failure class **without relying on the human or LLM coder remembering to run anything**. The same posture protects code regardless of who wrote it.