Add soft delete for revoked devices

Admins could only revoke devices, so never-enrolled and revoked
inventory rows piled up with no way to remove them. Soft-delete
is limited to REVOKED devices (revoke first), and ITAM GC now
hard-deletes PENDING/REVOKED orphans with no API key, postures,
or valid enrollment token—including user tombstones without
history.

Signed-off-by: Ludovic Vielle <ludovic@probo.com>

pkg/coredata/migrations/20260729T171926Z.sql

@@ -0,0 +1,35 @@
+-- Copyright (c) 2026 Probo Inc <hello@probo.com>.
+--
+-- Permission is hereby granted, free of charge, to any person obtaining a copy
+-- of this software and associated documentation files (the "Software"), to deal
+-- in the Software without restriction, including without limitation the rights
+-- to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+-- copies of the Software, and to permit persons to whom the Software is
+-- furnished to do so, subject to the following conditions:
+--
+-- The above copyright notice and this permission notice shall be included in
+-- all copies or substantial portions of the Software.
+--
+-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+-- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+-- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+-- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+-- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+-- SOFTWARE.
+
+ALTER TABLE devices
+    ADD COLUMN deleted_at TIMESTAMP WITH TIME ZONE;
+
+ALTER TABLE devices
+    ADD CONSTRAINT devices_deleted_at_check CHECK (
+        deleted_at IS NULL OR state = 'REVOKED'
+    );
+
+DROP INDEX devices_org_hardware_uuid_idx;
+
+CREATE UNIQUE INDEX devices_org_hardware_uuid_idx
+    ON devices (organization_id, hardware_uuid)
+    WHERE hardware_uuid IS NOT NULL
+      AND state != 'REVOKED'
+      AND deleted_at IS NULL;