The manifest lookup took the first composer.json at the root or inside a top directory, in zip order. Dist archives keep composer.json files for tests and examples, so tests/composer.json stored before the root file refused the push with a name mismatch. The root composer.json now always wins. Without one, the manifest inside a top directory is used only when there is exactly one; more than one refuses the archive as ambiguous.
Refs #134
checkCache answered nil both when a stored object couldn't be opened and after an integrity failure had cleared the record. Download handlers then fetched the upstream archive for the same version and filename, and recording it turned the pushed row into an upstream one without its manifest and queued the pushed object for deletion. One storage error while downloading a patched version served the unpatched upstream archive and dropped the push.
checkCache now looks at the record on a miss. For a pushed artifact it returns ErrHostedArtifactUnavailable when the object is recorded but couldn't be served, and ErrHostedArtifactMissing when no object is recorded any more. Every path that would fetch upstream goes through it, so none of them can replace the pushed artifact. Downloads answer 503 and 404 for the two.
Refs #133
Resolvers take a version's dependencies from the registry metadata, not from the archive, so listing a pushed version needs its manifest. A push now reads package.json from the top directory of an npm tarball, or composer.json from the root or the single top directory of a Composer zip, and keeps it in the new artifacts.manifest column (migration 013_add_artifact_manifest).
The manifest has to name the pushed package and version. A Composer manifest may leave the version out, and its name is compared case-insensitively. An archive that can't be read or whose manifest names something else is refused with 400 and removed from storage.
The version's integrity is now the archive's sha512, which npm clients expect in dist.integrity.
Refs #134
With hosted.enabled, PUT /api/hosted/{ecosystem}/{name}/{version} stores the request body as the archive for that version, marked local. It replaces any cached upstream copy and is served from the cache without contacting the upstream. GET /api/hosted/{ecosystem}/{name} lists what was pushed and DELETE removes a version again, after which clients get the upstream archive if there is one. Pushing and deleting need the bearer token; listing is open like the rest of the API.
Download handlers look archives up by the filename clients request, so a push is stored under the name its ecosystem derives from name and version: {name}-{version}.tgz for npm, without the scope, and {package}-{version}.zip for Composer. Other ecosystems are refused for now.
The Composer download handler resolves the upstream metadata before it looks at the cache and answers 404 for versions the upstream doesn't list. It now serves a pushed archive first. Only artifacts marked local take that path, so cached upstream archives still go through the metadata and commit checks.
The version's integrity is set to the pushed bytes, so the cache's integrity check verifies them rather than an upstream digest. Names and versions with path separators, dot segments or control characters are refused before anything is stored.
Refs #133
