feat: initial release — pdf-toolkit v1.0.0

Core operations:
- Compress PDF (3 presets: screen, ebook, printer, prepress)
- PDF/A detection and conversion to regular PDF
- Compress while preserving PDF/A structure
- Merge multiple PDFs
- Split/extract pages by range
- Rotate pages
- Extract text and images

Interface:
- Streamlit web GUI (app.py)
- FastAPI REST API with auto OpenAPI docs (api.py)

Docs:
- README.md, ARCHITECTURE.md, API.md
- Unit tests (15/15 passing)

scripts/run-web.sh

@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+# Inicia o pdf-toolkit via Streamlit
+set -e
+cd "$(dirname "$0")/.."
+echo "🌐 pdf-toolkit — Streamlit"
+echo "   Acesse: http://localhost:8550"
+exec streamlit run app.py --server.port 8550