Add the first upload API endpoint from PLAN.md. POST /api/uploads now
validates the requested file name, generates a server-owned upload id, creates
the staging and complete directory layout, and writes durable meta.json before
returning chunk scheduling details to the browser.
Keep filesystem layout knowledge in storage.rs so later chunk upload and
completion work can reuse the same boundary. API handlers translate storage
errors into JSON HTTP responses without leaking layout details into the router.
Document the new modules and UPL_DATA_DIR configuration, and extend TESTS.md
with the automated creation coverage.
Test Plan:
- just check
Refs: PLAN.md milestone 2
Introduce the first PLAN.md milestone: replace the hello-world binary with
an Axum server that binds to localhost by default, exposes a health endpoint,
and serves the static browser UI from the repository's static directory. The
router is available through the library crate so integration tests can exercise
server behavior without opening a network listener.
Add a justfile for routine validation and document the initial project shape,
configuration knobs, and reusable test checklist. The rustfmt config now uses
only stable options so the new formatting recipe runs without nightly warnings.
The upload API and resumable chunk behavior are intentionally left for later
milestones; the UI currently handles file selection only.
Test Plan:
- just check
Refs: PLAN.md milestone 1
ddidderr
