Spring-ai native hints for the pdf reader and for the open ai embeddings support

hi,

i needed the following graalvm native hints to make the pdf reader and the open ai embedding clients work in a graalvm aot native image context with Liberica NIK JDK. Please add them to their respective modules (KnuddelsHints and OpenAiEmbeddingsHints, I think , both belong near the openai support, and the PdfReaderHints belongs near the pdf document reader.) Just add them to the auto @Configuration class: @ImportRuntimeHints(KnuddelsHints.class), etc.

```java

static class KnuddelsHints implements RuntimeHintsRegistrar {

    @Override
    public void registerHints(RuntimeHints hints, ClassLoader classLoader) {
        hints.resources().registerResource(new ClassPathResource("/com/knuddels/jtokkit/cl100k_base.tiktoken"));
    }

}

static class OpenAiEmbeddingsHints implements RuntimeHintsRegistrar {

    @Override
    public void registerHints(RuntimeHints hints, ClassLoader classLoader) {
        var memberCategories = MemberCategory.values();
        for (var c : new Class[] { Embedding.class, EmbeddingRequest.class, EmbeddingResult.class })
            hints.reflection().registerType(c, memberCategories);

        hints.resources()
            .registerResource(new ClassPathResource("embedding/embedding-model-dimensions.properties"));
    }

}

static class PdfReaderHints implements RuntimeHintsRegistrar {

    @Override
    public void registerHints(RuntimeHints hints, ClassLoader classLoader) {
        try {

            var resolver = new PathMatchingResourcePatternResolver();

            var patterns = Set.of("/org/apache/pdfbox/resources/glyphlist/zapfdingbats.txt",
                    "/org/apache/pdfbox/resources/glyphlist/glyphlist.txt", "/org/apache/fontbox/cmap/**",
                    "/org/apache/pdfbox/resources/afm/**", "/org/apache/pdfbox/resources/glyphlist/**",
                    "/org/apache/pdfbox/resources/icc/**", "/org/apache/pdfbox/resources/text/**",
                    "/org/apache/pdfbox/resources/ttf/**", "/org/apache/pdfbox/resources/version.properties");

            for (var pattern : patterns)
                for (var resourceMatch : resolver.getResources(pattern))
                    hints.resources().registerResource(resourceMatch);

        }
        catch (IOException e) {
            throw new RuntimeException(e);
        }

    }

}

````