ci: adopt estate CI standard + convert 7 hand-rolled tests to PHPUnit (v0.7.0)

- Replace hand-rolled ci.yml jobs with thin caller to reusable estate workflow
  (peptiderepo/peptide-e2e/.github/workflows/ci.yml@main); tests: stubs; has_js: false.
  workflow_call + permissions: contents: write added per estate standard so deploy.yml
  can gate on it and phpcbf auto-commit step has required token scope.

- Convert 7 hand-rolled test-*.php scripts to PHPUnit TestCase classes:
    PeptideCptTest        <- test-peptide-cpt.php
    VerificationScannerTest <- test-verification-scanner.php
    VerificationSettingsTest <- test-verification-settings.php
    Migration0004Test     <- test-migration-0004.php
    JsonldTest            <- test-jsonld.php
    JsonldWebpageTest     <- test-jsonld-webpage.php
    JsonldPeptidePieceTest <- test-jsonld-peptide-piece.php

  All assertions preserved; old scripts remain in tests/unit/ but CI no longer
  runs them (PHPUnit discovery matches *Test.php only).

- Rewrite tests/bootstrap.php: full WP stub library for PHPUnit (WP_Post, WP_Error,
  all option/cron/CPT/taxonomy/permalink stubs); registers PR_Core_Autoloader.
- Add phpunit.xml.dist (bootstrap, unit suite, includes/ coverage).
- Add phpunit/phpunit ^9.6 + yoast/phpunit-polyfills ^2.0 to require-dev.
- Add composer test script (vendor/bin/phpunit --configuration phpunit.xml.dist).
- deploy.yml: add permissions: contents: write.
- Version bump 0.6.2 -> 0.7.0.

Agent-Session: claude-adopt-ci-20260616

.github/workflows/deploy.yml

@@ -4,8 +4,10 @@ on:
   push:
     branches: [ main ]
 
+# contents: write required so the ci.yml caller can pass write permission
+# through to the phpcbf auto-commit step in the reusable workflow.
 permissions:
-  contents: read
+  contents: write
 
 concurrency:
   group: deploy-peptide-repo-core