feat: Enhance campaign terms management with keyword addition and match type change functionality

- Added a toolbar for adding keywords in the campaign terms view.
- Implemented match type change functionality with a confirmation dialog.
- Added delete functionality for keywords with confirmation.
- Updated styles for new buttons and icons in the campaign terms view.
- Enhanced product view with warning icons for product alerts and corresponding modal display.
- Updated product table to include a new column for warnings and adjusted column visibility settings.
- Documented project overview, code style conventions, suggested commands, and task completion checklist.

.serena/memories/style_conventions.md

@@ -0,0 +1,9 @@
+# Code Style & Conventions
+
+- Spaces inside parentheses: `if ( $x )`, `function( $a, $b )`
+- Braces on new line for classes/functions
+- 4-space indent in classes, 2-space in templates
+- All controller/factory methods: `static public function`
+- JSON endpoints: `echo json_encode([...]); exit;`
+- Classes PascalCase, methods/variables/columns snake_case
+- Commit messages in Polish, prefixed with `feat:`, `fix:`, etc.