docker build . stamps the git tag or short commit, not dev (closes #154)

script/build writes the version script/version prints into
dist/package.json, which quak --version reports: the VERSION environment
variable or build arg when one is given, otherwise git describe --tags
--always, otherwise package.json's version. A checkout with .git whose
version comes out empty, dev or unknown fails the build.

.dockerignore no longer leaves out .git, and ARG VERSION has no default,
so a plain docker build . of a clone stamps its commit. script/docker and
script/cibuild still pass the host's version. make build-bin bundles the
built dist/, so the single binary reports the same version.

Model: opus-5-5

TODO.md

@@ -25,6 +25,15 @@ declares one.
 
 # Completed Steps
 
+- 2026-10-02: `docker build .` stamps the commit's tag or short commit, not
+  `dev` (issue 154). `script/build` writes the version `script/version` prints
+  into `dist/package.json`: the `VERSION` environment variable or build arg when
+  one is given, otherwise `git describe --tags --always`, otherwise the version
+  `package.json` declares. `.dockerignore` sends `.git`, and a checkout with
+  `.git` whose version comes out empty, `dev` or `unknown` fails the build.
+  `make build-bin` bundles the built `dist/`, so the single binary reports the
+  same version.
+
 - 2026-10-02: `photo.exif()` returns every EXIF tag in the file as `ExifTags`,
   keyed by tag name, each as exifreader decodes it, not only the thirteen common
   fields (issue 156). The embedded thumbnail's tags are under `Thumbnail`,