SCIM: users, groups, queries, PATCH, Bulk and cursors at /scim/v2, over x:Account (SCIM-1 to SCIM-57)

Every SCIM operation becomes the x:Account get, query or set JMAP makes,
as the service principal, so permissions, tenant scope and limits,
address uniqueness and account destruction are enforced in one place.
Discovery is anonymous; everything else takes an API key as a bearer
token and nothing else. Domains open to SCIM carry a flag in the domain
cache. Filters take eq and and, answered from the account indexes, with
unindexed attributes checked on at most 200 candidates. Cursors are
stateless, HMAC-sealed under the server key. PATCH applies to the
resource in memory and saves it as a PUT, so it is all or nothing.
Groups get an address from their display name on the principal's
domain; membership is written on each user.

Every write emits one of five new scim.* events (ids 637 to 641), also
added to the packaged schema. The helpers the surviving SCIM suites
import are rebuilt from the spec; scim_tests runs the new acceptance
suite and the surviving tenant isolation suite, and both pass.

crates/common/src/auth/mod.rs

@@ -69,7 +69,8 @@ pub struct DomainCache {
 
 pub const DOMAIN_FLAG_RELAY: u8 = 1;
 pub const DOMAIN_FLAG_SUB_ADDRESSING: u8 = 1 << 1;
-
+// inbuxa: SCIM-15, SCIM-58
+pub const DOMAIN_FLAG_SCIM: u8 = 1 << 2;
 
 #[derive(Debug, Clone, Default)]
 pub struct AccountCache {
@@ -329,4 +330,8 @@ impl DomainCache {
         self.names.first().map(|s| s.as_ref()).unwrap_or_default()
     }
 
+    // inbuxa: SCIM-15, SCIM-58
+    pub fn allows_scim(&self) -> bool {
+        self.flags & DOMAIN_FLAG_SCIM != 0
+    }
 }