Adopt reusable CI standard + PHPUnit suite (#8)

* feat(ci): adopt estate CI + add PHPUnit suite from scratch (v1.2.0)

- Add PHPUnit 9.6 test suite (WP stubs, tests: stubs) — 40 tests across 4 files:
  MathTest: 25 tests covering all PRC_Math public methods and calculate()
  orchestrator with real peptide scenarios (BPC-157/TB-500/Semaglutide/MK-677/
  Ipamorelin) plus edge cases (zero water, negative inputs, floor rounding,
  rounding precision, mcg↔mg conversion).
  DefaultPresetsTest: 11 tests — all 8 expected slugs, required keys per preset
  (dataProvider), dose_unit validity, min<max range, source field, spot-checks.
  RestControllerTest: 7 tests — calculate() 200 + correct values (mcg+mg),
  get_presets() 200, get_preset() 200 for known slug / WP_Error for unknown.
  PresetProviderTest: 4 tests — fallback to defaults sans PR Core, slug key
  present, cache invalidation, idempotent invalidation.
- Add phpunit.xml.dist + tests/bootstrap.php (WP function/class stubs).
- Add composer test script: vendor/bin/phpunit --configuration phpunit.xml.dist.
- Add phpunit/phpunit ^9.6 + yoast/phpunit-polyfills ^2.0 to require-dev.
- Replace standalone ci.yml with thin caller to estate reusable workflow:
  uses: peptiderepo/peptide-e2e/.github/workflows/ci.yml@main
  with: tests: stubs, has_js: true
  permissions: contents: write (required for phpcbf commit-back)
  workflow_call (required for deploy.yml gate).
- deploy.yml unchanged — already gates on ./ci.yml + uses shared deploy-app.yml.
- Version bump 1.1.0 → 1.2.0.

Agent-Session: claude/adopt-ci-20260616

* style: auto-fix PHPCS violations via phpcbf

* fix(ci): resolve latent PHPCS + JS lint failures

Latent debt surfaced by the reusable PHPCS job (previously continue-on-error).

PHPCS fixes (all pre-existing, not introduced by this PR):
- Add @package PeptideReconstitutionCalculator to file docblocks in all 12 PHP
  files (previously missing; phpcbf cannot insert missing docblock tags).
- Replace two short-ternary ?: operators in class-prc-preset-provider.php with
  full ternary (Universal.Operators.DisallowShortTernary.Found; lines 136+152).

JS lint fix:
- Add package.json + package-lock.json (no deps; lint script = node --check)
  so the reusable lint-js job's npm ci / cache: npm steps succeed. The
  calculator ships vanilla JS with no build toolchain — package.json is the
  minimal stub the reusable workflow requires for has_js: true.

Agent-Session: claude/adopt-ci-20260616

* style: auto-fix PHPCS violations via phpcbf

* fix(phpcs): suppress intentional warnings with phpcs:ignore annotations

uninstall.php: direct wpdb->query() intentional in uninstall (no caching
available); add phpcs:ignore DirectDatabaseQuery.DirectQuery and NoCaching.
class-prc-rest-controller.php get_presets(): request param required by
WP REST API callback contract; add phpcs:ignore UnusedFunctionParameter.

Agent-Session: claude/adopt-ci-20260616

---------

Co-authored-by: peptiderepo <bot@peptiderepo.com>
Co-authored-by: peptiderepo <peptiderepo@users.noreply.github.com>

includes/class-prc-calculator.php

@@ -9,6 +9,7 @@
  * @see class-prc-shortcode.php    — Frontend calculator widget.
  * @see class-prc-rest-controller.php — REST endpoints for presets.
  * @see class-prc-preset-provider.php — PR Core integration + fallback defaults.
+ * @package PeptideReconstitutionCalculator
  */
 
 declare(strict_types=1);
@@ -29,17 +30,17 @@ class PRC_Calculator {
 	public static function boot(): void {
 		// Frontend shortcode — always available.
 		$shortcode = new PRC_Shortcode();
-		add_action( 'init', [ $shortcode, 'register' ] );
+		add_action( 'init', array( $shortcode, 'register' ) );
 
 		// REST API — serves presets to the JS calculator.
-		add_action( 'rest_api_init', [ new PRC_Rest_Controller(), 'register_routes' ] );
+		add_action( 'rest_api_init', array( new PRC_Rest_Controller(), 'register_routes' ) );
 
 		// Cache invalidation — keep presets in sync with PR Core dosing data.
 		PRC_Cache_Listener::register();
 
 		// Admin notice when PR Core is absent.
 		if ( is_admin() && ! self::is_pr_core_active() ) {
-			add_action( 'admin_notices', [ __CLASS__, 'render_pr_core_notice' ] );
+			add_action( 'admin_notices', array( __CLASS__, 'render_pr_core_notice' ) );
 		}
 	}
 
@@ -70,7 +71,7 @@ class PRC_Calculator {
 		}
 
 		// Only show on plugins page and the calculator's own pages.
-		$show_on = [ 'plugins', 'settings_page_prc-settings' ];
+		$show_on = array( 'plugins', 'settings_page_prc-settings' );
 		if ( ! in_array( $screen->id, $show_on, true ) ) {
 			return;
 		}