refactor: split TextReplacer into HtmlTokens and StoredForms (M1)

- HtmlTokens (static, with the S45 docblock): SPLIT, RAW_OPEN, tokenize(),
  structure(), closes(), unterminated() moved unchanged; new RAW_ELEMENTS list.
- StoredForms: of() (was TextReplacer::forms), mentions(), unicodeEscaped() –
  the DB prefilter forms; TextReplacer::mentions() delegates, the ability's
  candidate query uses StoredForms::of().
- TextReplacer keeps problems(), apply() and the splice/safe() verification;
  safe() still runs the tokenizer and HtmlContext as two independent scans, in
  the same order.
HtmlTokensTest asserts RAW_ELEMENTS === HtmlContext::RAW and that RAW_OPEN opens
exactly those elements. TextReplacerTest and HtmlContextTest unchanged.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01At3V6SjwbMe6eMzVGW3Hs7

tests/Unit/Integrations/Divi/Compose/HtmlTokensTest.php

@@ -0,0 +1,34 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Tests\Unit\Integrations\Divi\Compose;
+
+use LIT\MCP\Integrations\Divi\Compose\HtmlContext;
+use LIT\MCP\Integrations\Divi\Compose\HtmlTokens;
+use PHPUnit\Framework\TestCase;
+
+/** Ruling S45: the tokenizer and the independent scan (HtmlContext) share one raw-text element list. */
+final class HtmlTokensTest extends TestCase
+{
+    public function testRawElementsAreHtmlContextsList(): void
+    {
+        self::assertSame(HtmlContext::RAW, HtmlTokens::RAW_ELEMENTS);
+    }
+
+    /** RAW_OPEN opens exactly the RAW_ELEMENTS: their body is "raw", other elements' body is text. */
+    public function testRawOpenMatchesTheList(): void
+    {
+        foreach (HtmlTokens::RAW_ELEMENTS as $element) {
+            $tokens = HtmlTokens::tokenize('<' . strtoupper($element) . ' a="1">x</' . $element . '>y');
+            // plaintext never ends: everything after it stays raw.
+            $after = $element === 'plaintext' ? 'raw' : 'text';
+            self::assertSame(['token', 'raw', 'token', $after], array_column((array) $tokens, 0), $element);
+        }
+
+        foreach (['div', 'scripts', 'styles', 'textarea', 'title'] as $element) {
+            $tokens = HtmlTokens::tokenize('<' . $element . '>x</' . $element . '>');
+            self::assertSame(['token', 'text', 'token'], array_column((array) $tokens, 0), $element);
+        }
+    }
+}