Implement versiond M1: inotify monitor, versioning, diff, restore, systemd install

FastAPI service on 127.0.0.1:9922 that monitors user-chosen directories
with pruned inotify watches, stores versions in a local content-addressed
spool indexed in SQLite, coalesces bursts (first + last), and offers
history, diff and dry-run-first bulk restore. Includes a CLI with a
systemd user unit installer.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

pyproject.toml

@@ -0,0 +1,27 @@
+[build-system]
+requires = ["setuptools>=69"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name = "versiond"
+version = "0.1.0"
+description = "Local file versioning and backup service"
+readme = "readme.md"
+requires-python = ">=3.12"
+dependencies = [
+    "fastapi>=0.110",
+    "uvicorn>=0.29",
+    "asyncinotify>=4.0",
+]
+
+[project.optional-dependencies]
+dev = ["pytest>=8", "httpx>=0.27"]
+
+[project.scripts]
+versiond = "versiond.cli:main"
+
+[tool.setuptools.packages.find]
+where = ["src"]
+
+[tool.pytest.ini_options]
+testpaths = ["tests"]