chore(api): Regenerate the build API plumbing

README.md

@@ -371,6 +371,8 @@ A build runs on the remote build service, in a builder of your own account, from
 sources the builder fetches itself: a git repository or a tarball, never a directory on
 this machine. A create takes the properties the API describes; `kraftfile_from` reads
 the Kraftfile out of a source, and `image_output` pushes the image with your token.
+Without a `kraftfile`, the build is the `Dockerfile` in the context on the
+`base-compat:latest` runtime.
 `logs()` follows the progress as buildkit events, every event once, asking again and
 skipping what it has seen when the stream is cut, and ends with the event that carries
 the `result` or the `error`: a failed build is that last event, not an exception.

src/unikraft_cloud/resources/builds.py

@@ -2,11 +2,12 @@
 # Copyright (c) 2026, Unikraft GmbH. All rights reserved.
 #
 # Builds on the remote build service: a request names the sources, the
-# Kraftfile and the outputs, the build runs on a builder in the caller's own
-# account, and its progress can be followed from the start until it ends. The
-# service is global, so no metro scope applies. Every source is a git
-# repository or a tarball the builder fetches itself: a directory on this
-# machine would need a buildkit session, which the service does not take yet.
+# outputs and a Kraftfile, or no Kraftfile to build the context's Dockerfile
+# alone; the build runs on a builder in the caller's own account, and its
+# progress can be followed from the start until it ends. The service is
+# global, so no metro scope applies. Every source is a git repository or a
+# tarball the builder fetches itself: a directory on this machine would need
+# a buildkit session, which the service does not take yet.
 
 from __future__ import annotations
 
@@ -165,6 +166,8 @@ def __init__(self, session: Session) -> None:
     async def create(self, *, timeout: TimeoutOption = UNSET, **spec: Any) -> Build:
         """Create a build from the properties the API describes; it runs whether or not followed.
 
+        Without a ``kraftfile``, the build is the ``Dockerfile`` in the
+        ``context`` on the ``base-compat:latest`` runtime, for ``x86_64``.
         A property the API does not describe is a ``TypeError``. The service
         refuses a request that uses a part of the API it does not support yet
         with the code ``unsupported``, and a tenant with as many builds