Add project variants and UI updates

migrations/026_add_project_variant.sql

@@ -0,0 +1,28 @@
+-- Add project variant and reset codes from project names
+
+ALTER TABLE qt_projects
+    ADD COLUMN variant VARCHAR(100) NOT NULL DEFAULT '' AFTER code;
+
+-- Drop legacy unique index on code to allow duplicate codes
+DROP INDEX IF EXISTS idx_qt_projects_code ON qt_projects;
+DROP INDEX IF EXISTS idx_qt_projects_code_variant ON qt_projects;
+
+-- Reset code from name and clear variant
+UPDATE qt_projects
+SET code = LEFT(TRIM(COALESCE(name, '')), 100),
+    variant = '';
+
+-- De-duplicate by assigning variant numbers: -2, -3...
+UPDATE qt_projects p
+JOIN (
+    SELECT p1.id,
+           p1.code,
+           (SELECT COUNT(*)
+            FROM qt_projects p2
+            WHERE p2.code = p1.code AND p2.id <= p1.id) AS rn
+    FROM qt_projects p1
+) r ON r.id = p.id
+SET p.code = r.code,
+    p.variant = CASE WHEN r.rn = 1 THEN '' ELSE CONCAT('-', r.rn) END;
+
+CREATE UNIQUE INDEX idx_qt_projects_code_variant ON qt_projects(code, variant);