Rename the identifiers that carried the upstream name

Everything clients, users and operators meet now carries the fork's name,
with no aliases (SPEC.md §2.4, changed here from "protocol identifiers
stay"):

- JMAP: upstream's registry capability is urn:inbuxa:jmap:registry, beside
  the fork's own urn:inbuxa:jmap.
- WebDAV lock and sync tokens are urn:inbuxa:dav*; clients resync once.
- Sieve: vnd.inbuxa.while and vnd.inbuxa.expressions. sieve-rs spells these
  into its compiler, so it's vendored (vendor/sieve-rs, 0.7.3) and patched in;
  a unit test fails if Cargo.lock ever moves past the vendored copy. The
  trusted runtime now names itself too, rather than answering sieve-rs's
  default.
- The web interface's OAuth client is inbuxa-webui. On every start the old
  stalwart-webui client is removed and any application naming it is moved
  over.
- The spam filter's blobs are INBUXA_SPAM_*; every start moves any left
  under the old keys, so a trained model survives.
- SQL stores and log files default to inbuxa, in the code and in the
  schema served to the admin (checksum regenerated).
- Settings are INBUXA_* only. A STALWART_* variable that's set where its
  INBUXA_* one isn't stops the server at startup, naming it.
- The version-upgrade messages link docs.inbuxa.org's migration page, and
  the OpenAPI description, smtp crate metadata and web-push test fixtures
  lose the name.

Kept on purpose, allowlisted with reasons: the OAuth key-derivation
contexts (renaming them would end every session and invalidate every
sealed client id) and the hashed application prefix.

Also fixes a latent start-up failure: ensure_client updated an existing
first-party client with a revision of 0, which the registry's assertion
never matches, so adding a redirect URI or changing the webmail secret
failed start-up. And the principal session test now expects
legacyProtocols (C-1, added 2026-09-21), which it had missed.

Tested: the server builds without warnings; common's 106 unit tests,
including the vendoring check; a new integration test for the two
start-up migrations; and the webdav, jmap, imap and SMTP Sieve suites.

crates/registry/src/schema/enums_impl.rs

@@ -2,6 +2,8 @@
  * SPDX-FileCopyrightText: 2020 Stalwart Labs LLC <hello@stalw.art>
  *
  * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-SEL
+ *
+ * Modified by Coffey Labs in 2026 for INBUXA.
  */
 
 // This file is auto-generated. Do not edit directly.
@@ -10372,8 +10374,8 @@ impl EnumImpl for SieveCapability {
             b"spamtest" => SieveCapability::Spamtest,
             b"spamtestplus" => SieveCapability::Spamtestplus,
             b"virustest" => SieveCapability::Virustest,
-            b"vnd.stalwart.while" => SieveCapability::VndStalwartWhile,
-            b"vnd.stalwart.expressions" => SieveCapability::VndStalwartExpressions,
+            b"vnd.inbuxa.while" => SieveCapability::VndStalwartWhile,
+            b"vnd.inbuxa.expressions" => SieveCapability::VndStalwartExpressions,
         }
     }
 
@@ -10426,8 +10428,8 @@ impl EnumImpl for SieveCapability {
             SieveCapability::Spamtest => "spamtest",
             SieveCapability::Spamtestplus => "spamtestplus",
             SieveCapability::Virustest => "virustest",
-            SieveCapability::VndStalwartWhile => "vnd.stalwart.while",
-            SieveCapability::VndStalwartExpressions => "vnd.stalwart.expressions",
+            SieveCapability::VndStalwartWhile => "vnd.inbuxa.while",
+            SieveCapability::VndStalwartExpressions => "vnd.inbuxa.expressions",
         }
     }