Drop legacy document columns and approver tables

The title, classification, and document_type columns have been moved to
document_versions. The document_approvers and document_version_approvers
tables have been replaced by approval quorums and decisions.

Signed-off-by: Sacha Al Himdani <sacha@getprobo.com>

pkg/coredata/migrations/20260319T160000Z.sql

@@ -104,6 +104,3 @@ LEFT JOIN document_approvers da ON da.document_id = dv.document_id
 WHERE dv.status = 'PUBLISHED'
     AND COALESCE(dva.approver_profile_id, da.approver_profile_id) IS NOT NULL
 ON CONFLICT (quorum_id, approver_id) DO NOTHING;
-
--- TODO: DROP TABLE document_version_approvers once confirmed safe
--- TODO: DROP TABLE document_approvers once confirmed safe

pkg/coredata/migrations/20260328T120000Z.sql

@@ -1,2 +1 @@
--- TODO: drop the classification column from documents.
 ALTER TABLE documents ALTER COLUMN classification SET DEFAULT 'SECRET';

pkg/coredata/migrations/20260331T120000Z.sql

@@ -8,5 +8,4 @@ WHERE dv.document_id = d.id;
 
 ALTER TABLE document_versions ALTER COLUMN document_type DROP DEFAULT;
 
--- TODO: drop the document_type column from documents.
 ALTER TABLE documents ALTER COLUMN document_type SET DEFAULT 'OTHER';

pkg/coredata/migrations/20260407T120000Z.sql

@@ -12,7 +12,6 @@
 -- OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 -- PERFORMANCE OF THIS SOFTWARE.
 
--- TODO: drop the title column from documents.
 ALTER TABLE documents ALTER COLUMN title DROP NOT NULL;
 
 ALTER TABLE documents DROP COLUMN description;

pkg/coredata/migrations/20260409T130000Z.sql

@@ -0,0 +1,22 @@
+-- Copyright (c) 2026 Probo Inc <hello@getprobo.com>.
+--
+-- Permission to use, copy, modify, and/or distribute this software for any
+-- purpose with or without fee is hereby granted, provided that the above
+-- copyright notice and this permission notice appear in all copies.
+--
+-- THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+-- REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+-- AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+-- INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+-- LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+-- OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+-- PERFORMANCE OF THIS SOFTWARE.
+
+-- Drop legacy columns from documents that have been moved to document_versions.
+ALTER TABLE documents DROP COLUMN title;
+ALTER TABLE documents DROP COLUMN classification;
+ALTER TABLE documents DROP COLUMN document_type;
+
+-- Drop legacy approver tables replaced by approval quorums/decisions.
+DROP TABLE document_version_approvers;
+DROP TABLE document_approvers;