## What it does
Moves the existing public API implementation files to `*php*` sidecar
filenames with no line changes.
This is intentionally only a file-move PR. It does not add public
loaders, native wrapper classes, or behavior changes; those stay in the
stacked PR #271.
## Rationale
This gives reviewers a clean baseline where GitHub shows the large
implementation files as renames before #271 adds the native integration
and loader changes.
## Implementation
Moved these files at 100% similarity:
- `components/HTML/class-wp-html-tag-processor.php` ->
`components/HTML/class-wp-html-php-tag-processor.php`
- `components/HTML/class-wp-html-processor.php` ->
`components/HTML/class-wp-html-php-processor.php`
- `components/XML/class-xmlprocessor.php` ->
`components/XML/class-phpxmlprocessor.php`
- `components/DataLiberation/URL/class-urlintextprocessor.php` ->
`components/DataLiberation/URL/class-phpurlintextprocessor.php`
The class names are deliberately unchanged in this PR so the diff
remains move-only.
## Testing instructions
```bash
composer dump-autoload
php -l components/HTML/class-wp-html-php-tag-processor.php components/HTML/class-wp-html-php-processor.php components/XML/class-phpxmlprocessor.php components/DataLiberation/URL/class-phpurlintextprocessor.php
vendor/bin/phpunit components/XML/Tests/
vendor/bin/phpunit components/DataLiberation/Tests/URLInTextProcessorTest.php
vendor/bin/phpunit components/DataLiberation/Tests/MarkupProcessorConsumerTest.php components/DataLiberation/Tests/HTMLEntityReaderTest.php
vendor/bin/phpunit components/Markdown/Tests/MarkdownConsumerTest.php
git diff origin/trunk...HEAD --check
```