feat: Initial commit for Saqel Platform architecture, backend, Docker, and documentation

backend/.agents/skills/testing-best-practices/rules/finding-features.md

@@ -0,0 +1,35 @@
+# How to Find Test Framework Features
+
+PHPUnit and Laravel provide features for most testing needs. Find an existing feature before implementing the behavior by hand.
+
+- Give `search-docs` the capability you need rather than the name of a method you remember. It returns Laravel testing documentation for the installed version.
+- Fetch `https://phpunit.de/documentation.html` for version-specific PHPUnit attributes, assertions, and command-line options.
+- If a search returns no results, tell the user that the installed version does not provide the feature. Do not write an API that you have not confirmed.
+
+Search for a feature in this table before you write the code by hand.
+
+| Work that you need | Term to search for |
+| --- | --- |
+| Run one test method with many input values | data provider, `#[DataProvider]`, `#[TestWith]` |
+| Run one test only after another test passes | `#[Depends]` |
+| Select or skip a set of tests in one run | `#[Group]`, `--group`, `--exclude-group` |
+| Skip a test on a version or on a missing extension | `#[RequiresPhp]`, `#[RequiresPhpExtension]` |
+| Find a test that depends on the order of the run | `--order-by=random` |
+| Reduce the time of a slow suite | ParaTest, `--cache-result` |
+| Stop the run at the first failure while you debug | `--stop-on-failure`, `--filter` |
+
+## The Assertions of Laravel
+
+Laravel provides assertions for each part of the framework. Fetch `https://laravel.com/framework/docs/testing` for the complete list, and search for an assertion before building a check by hand. Examples include `assertDatabaseHas()`, `assertModelExists()`, `assertSoftDeleted()`, response assertions such as `assertRedirectToRoute()` and `assertJsonPath()`, and fake assertions such as `Queue::assertPushed()` and `Notification::assertSentTo()`.
+
+A hand-built check fails with `false is not true`, which identifies nothing. A framework assertion names the incorrect table, value, or response, so the failure indicates what to fix.
+
+```php
+// The failure says that false is not true.
+// Instead of this
+$this->assertTrue(User::where('email', 'taylor@laravel.com')->exists());
+
+// Use this
+// The failure names the table and the attributes that it did not find.
+$this->assertDatabaseHas('users', ['email' => 'taylor@laravel.com']);
+```