Add Deck workflow automation Nextcloud app

Ports the standalone due-date cron script into a proper Nextcloud 34
app with a personal-settings UI, per-user workflow configuration
(source/target stack, assigned-user and label filters, email
notification), a TimedJob background runner, and Gitea CI pipelines.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

tests/Unit/Service/WorkflowRunnerFilterTest.php

@@ -0,0 +1,46 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OCA\WorkflowDeckAutomation\Tests\Unit\Service;
+
+use OCA\WorkflowDeckAutomation\Service\WorkflowRunner;
+use PHPUnit\Framework\TestCase;
+
+class WorkflowRunnerFilterTest extends TestCase {
+	public function testIsOverdueReturnsFalseWithoutDueDate(): void {
+		$this->assertFalse(WorkflowRunner::isOverdue(null));
+	}
+
+	public function testIsOverdueReturnsFalseForFutureDueDate(): void {
+		$this->assertFalse(WorkflowRunner::isOverdue(0));
+		$this->assertFalse(WorkflowRunner::isOverdue(3));
+	}
+
+	public function testIsOverdueReturnsTrueForPastDueDate(): void {
+		$this->assertTrue(WorkflowRunner::isOverdue(-1));
+		$this->assertTrue(WorkflowRunner::isOverdue(-30));
+	}
+
+	public function testNoFiltersMatchesAnyCard(): void {
+		$this->assertTrue(WorkflowRunner::cardMatchesFilters(['alice'], [1, 2], [], []));
+		$this->assertTrue(WorkflowRunner::cardMatchesFilters([], [], [], []));
+	}
+
+	public function testUserFilterIsOrAgainstAssignedUsers(): void {
+		$this->assertTrue(WorkflowRunner::cardMatchesFilters(['alice', 'bob'], [], ['bob', 'carol'], []));
+		$this->assertFalse(WorkflowRunner::cardMatchesFilters(['alice'], [], ['bob', 'carol'], []));
+	}
+
+	public function testLabelFilterIsOrAgainstCardLabels(): void {
+		$this->assertTrue(WorkflowRunner::cardMatchesFilters([], [1, 2], [], [2, 3]));
+		$this->assertFalse(WorkflowRunner::cardMatchesFilters([], [1], [], [2, 3]));
+	}
+
+	public function testUserAndLabelFiltersAreCombinedWithAnd(): void {
+		// user matches, label does not -> overall false
+		$this->assertFalse(WorkflowRunner::cardMatchesFilters(['alice'], [1], ['alice'], [99]));
+		// both match -> true
+		$this->assertTrue(WorkflowRunner::cardMatchesFilters(['alice'], [1], ['alice'], [1]));
+	}
+}