Add BaseSettingsRESTController for plugin-ui settings (#3)

* Add BaseSettingsRESTController for schema-driven settings management

Introduces an abstract REST controller compatible with @wedevs/plugin-ui
<Settings> component. Includes variant-aware validation and sanitization,
permission checks with WP_Error, deep-merge persistence to wp_options,
and comprehensive apply_filters/do_action hooks for extensibility.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Add Settings controller documentation to developer guide

Documents BaseSettingsRESTController usage: creating a controller,
defining schemas, supported field variants, translatable messages,
extending settings via hooks, and the full hook reference table.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Add CLAUDE.md config and exclude dev files from composer exports

Adds project context for Claude Code, .gitattributes with export-ignore
for CLAUDE.md, .claude/, tests/, docs/, and config files so consumer
plugins don't receive them via composer install.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Fix PHPCS violations in BaseSettingsRESTController

Add file doc comment, fix Yoda conditions, multi-line function call
formatting, short ternary usage, and missing doc comment descriptions.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Fix number sanitization to preserve decimal values

Use floatval() for decimal numbers and intval() for integers instead
of always truncating with intval(). Also remove file doc comment.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Add file doc comment to BaseSettingsRESTController

Required by PHPCS Squiz.Commenting.FileComment rule.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: mrabbani

.gitattributes

@@ -0,0 +1,10 @@
+# Exclude from composer archive/install (export-ignore)
+/.gitattributes     export-ignore
+/.gitignore         export-ignore
+/CLAUDE.md          export-ignore
+/.claude/           export-ignore
+/tests/             export-ignore
+/docs/              export-ignore
+/.phpcs.xml.dist    export-ignore
+/phpunit.xml        export-ignore
+/phpunit.xml.dist   export-ignore

.gitignore

@@ -2,3 +2,4 @@
 composer.lock
 .phpunit.cache/
 .phpunit.result.cache
+.claude/

CLAUDE.md

@@ -0,0 +1,62 @@
+# WPKit - Claude Code Configuration
+
+## Project Overview
+
+**wedevs/wp-kit** is a standalone WordPress PHP toolkit providing DataLayer, Cache, Migration, Admin Notification, and Settings components. It is a Composer library consumed by WordPress plugins (e.g., Dokan). It has no WooCommerce dependency.
+
+- **Namespace:** `WeDevs\WPKit\`
+- **Source:** `src/`
+- **Tests:** `tests/phpunit/tests/`
+- **Docs:** `docs/developer-guide.md`
+- **PHP:** 7.4+
+
+## Architecture
+
+- This is a **library package**, not a plugin. It must never hardcode text domains, plugin slugs, or assume a specific consumer.
+- All translatable strings must be overridable by consumers via methods or filters. Never use `__()` or `esc_html__()` directly — provide overridable methods instead.
+- All WordPress hooks use the consumer-provided prefix (e.g., `option_prefix`). No library-level hook prefixes.
+- Classes are abstract base classes meant to be extended by consumer plugins.
+
+## Coding Standards
+
+- Follow WordPress Coding Standards (WPCS). Run `composer phpcs` to check.
+- Use WordPress PHP functions for sanitization (`sanitize_text_field`, `sanitize_key`, `absint`, etc.) and escaping (`esc_html`, `esc_attr`, etc.).
+- Use tabs for indentation (WordPress standard).
+- PHPDoc blocks on all public and protected methods.
+- Type hints on parameters and return types where PHP 7.4 allows.
+
+## Key Conventions
+
+- **Hooks:** Use `apply_filters` and `do_action` at key extension points. Namespace hooks with the consumer's prefix property (e.g., `"{$this->option_prefix}_settings_schema"`).
+- **REST Controllers:** Extend `WP_REST_Controller`. Permission callbacks must return `true` or `WP_Error` (never bare `false`). Provide overridable methods for error messages.
+- **Options Storage:** Use `wp_options` with consumer-defined prefixes. Always `sanitize_key()` user-provided keys before building option names.
+- **Validation:** Provide sensible default validation. Allow consumers to override via subclass methods and filters.
+
+## Commands
+
+- `composer test` — Run PHPUnit tests
+- `composer phpcs` — Run PHP CodeSniffer
+- `composer phpcbf` — Auto-fix coding standards
+- `composer lint` — Alias for phpcs
+
+## Testing
+
+- Tests use PHPUnit 9/10 with Brain\Monkey for WordPress function mocking.
+- Test namespace: `WeDevs\WPKit\Tests\`
+- Test directory: `tests/phpunit/tests/`
+
+## File Structure
+
+```
+src/
+├── AdminNotification/   # Notice system (providers, manager, REST)
+├── Cache/               # Caching layer
+├── DataLayer/           # Models, DataStores, SQL builder
+├── Migration/           # Schema migrations, background processing
+└── Settings/            # Schema-driven settings REST controller
+docs/
+└── developer-guide.md   # Comprehensive developer documentation
+tests/
+└── phpunit/
+    └── tests/           # PHPUnit test files
+```