build: scope sdist to package, sites, tests, and docs

Untracked workspace/, dev/, .opencode/, and SQLite WAL files were
being swept into the source distribution (5.3 MB → 151 KB).

pyproject.toml

@@ -30,6 +30,17 @@ build-backend = "hatchling.build"
 [tool.hatch.build.targets.wheel]
 packages = ["gimme_job"]
 
+[tool.hatch.build.targets.sdist]
+include = [
+    "/gimme_job",
+    "/sites",
+    "/tests",
+    "/README.md",
+    "/pyproject.toml",
+    "/uv.lock",
+    "/.env.example",
+]
+
 [dependency-groups]
 dev = [
     "pytest>=8.0",