New docs

docs/getting-started/build-and-run.md

@@ -1,2 +1,46 @@
 # Build and run
 
+## Build
+
+Debug (default):
+
+```sh
+dcr build
+# or
+dcr build --debug
+```
+
+Release:
+
+```sh
+dcr build --release
+```
+
+## Run
+
+```sh
+dcr run
+# or
+dcr run --release
+```
+
+`dcr run` first builds, then launches the produced binary.
+
+## Clean artifacts
+
+```sh
+dcr clean
+```
+
+Profile-only cleanup:
+
+```sh
+dcr clean --debug
+dcr clean --release
+```
+
+## Notes
+
+- `run` is unavailable for `build.kind = "staticlib"`.
+- Build profile flag is parsed from the first command argument.
+- Unknown profile flags produce an error.