Add project variants and UI updates

migrations/025_add_project_code.sql

@@ -0,0 +1,38 @@
+-- Add project code and enforce uniqueness
+
+ALTER TABLE qt_projects
+    ADD COLUMN code VARCHAR(100) NULL AFTER owner_username;
+
+-- Copy code from current project name (truncate to fit)
+UPDATE qt_projects
+SET code = LEFT(TRIM(COALESCE(name, '')), 100);
+
+-- Fallback for any remaining blanks
+UPDATE qt_projects
+SET code = uuid
+WHERE code IS NULL OR TRIM(code) = '';
+
+-- Drop unique index if it already exists to allow de-duplication updates
+DROP INDEX IF EXISTS idx_qt_projects_code ON qt_projects;
+
+-- De-duplicate codes: OPS-1948-2, OPS-1948-3... (MariaDB without CTE)
+UPDATE qt_projects p
+JOIN (
+    SELECT p1.id,
+           p1.code AS base_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 = CASE
+    WHEN r.rn = 1 THEN r.base_code
+    ELSE CONCAT(LEFT(r.base_code, 90), '-', r.rn)
+END;
+
+ALTER TABLE qt_projects
+    MODIFY COLUMN code VARCHAR(100) NOT NULL;
+
+CREATE UNIQUE INDEX idx_qt_projects_code ON qt_projects(code);