Fix container build for sharp, slug lookup and select fields

- build the runtime image so libvips lands next to the sharp binary
- GET /api/v1/posts/:slug finds drafts by slug for write clients
- media upload documented with project slug instead of a project id
- own select control instead of the browser default
- quieter sidebar footer, project name leads to its entries

src/lib/admin-routes.ts

@@ -16,6 +16,10 @@ export function adminApiFilePath(file: 'openapi' | 'style-guide'): Route {
 	return `/admin/api/files/${file}` as Route
 }
 
+export function adminProjectEntriesPath(slug: string): Route {
+	return `${adminEntriesPath}?project=${encodeURIComponent(slug)}` as Route
+}
+
 export function adminPostTypePath(id: string): Route {
 	return `/admin/post-types/${encodeURIComponent(id)}` as Route
 }