v0.7.0 - brand identity, S3 file storage, storage quotas

Added

• Brand identity: the Open Artifacts logo now appears on the login/register pages (with a dark-theme wordmark variant), the sidebar rail and mobile header, and as the browser favicon/apple-touch-icon. Generated from a single source image via scripts/gen-brand-assets.sh (ImageMagick), checked in alongside it for reproducibility.
• S3-compatible file storage for artifacts: images and other files can now be uploaded and attached to an artifact — POST /api/v1/artifacts/:id/files (multipart/form-data), GET .../files to list, DELETE .../files/:fileId to remove, served back through the app at GET /af/:token (never a public bucket, no presigned URLs). oa files upload|ls|rm on the CLI; list_artifact_files/delete_artifact_file as MCP tools (uploading itself is CLI/REST-only — MCP tool calls are JSON, not multipart). A file is always attached to exactly one artifact and is deleted with it (explicit delete, expiry, or an org being deleted all queue its object for removal); a file with no artifact cannot exist. docker-compose.yml now bundles a MinIO service as the default storage backend; point S3_ENDPOINT/S3_BUCKET/S3_ACCESS_KEY_ID/S3_SECRET_ACCESS_KEY at an external S3/R2/Spaces bucket instead, or leave S3_BUCKET unset to disable the feature entirely (upload endpoints answer 501, everything else is unaffected).
• Storage quotas, instance- and team-wide: two new limits — total bytes per team and bytes per single artifact (both counting artifact source text plus uploaded files) — configurable instance-wide in /admin/settings and, per team, in its own team settings (the per-artifact one by an owner/admin, the team-wide one by a superadmin, matching the existing permission split for other org-level knobs). A team override can only ever be equal-or-stricter than the instance ceiling, never looser. Default: unlimited at both levels (see Changed below).
• GET /api/v1/quota (and the get_storage_quota MCP tool / oa quota CLI command): lets an agent check remaining quota — team-wide, or narrowed to one artifact — before deciding whether to upload a file, rather than uploading blindly and handling the failure after the fact.
• quota_exceeded is now a structured error (scope, limitBytes, usedBytes) instead of a flat message, on both the REST API and MCP tools, so a caller can act on it instead of just displaying it.

Changed

• Breaking: a team's storage quota now defaults to unlimited instead of 1 GiB. Any team whose quota was never explicitly changed by a superadmin (i.e. still sitting at exactly the old 1 GiB default) is migrated to "inherit the instance quota" (itself unlimited by default); a team a superadmin deliberately set to a specific number keeps that number. orgs.storageQuotaBytes also changed from a required column to nullable (null = inherit) and from integer to bigint, since it now also counts uploaded file bytes, not just artifact source text.
• Fixed a latent bug in the instance's own "maximum artifact size" setting (InstanceSettings.maxArtifactSizeBytes): it was editable in the admin UI and accepted by PATCH /admin/settings, but nothing ever read it back — artifact-size enforcement used a hardcoded 5 MiB constant regardless. It's now a required, resolved parameter on every artifact-creating/updating code path, the same pattern already used for artifact lifetime.

Fixed

• Every "copy" button silently did nothing on insecure (plain HTTP) origins, or wherever the browser/embedder denied navigator.clipboard — that API is undefined or rejects in those cases without surfacing an error. Added a shared copyToClipboard() helper with an execCommand('copy') fallback, used by CopyButton and the public share page's own inline copy-link script.