docs: add YAML example to PromptBuilder documentation

Author: ritikraj2425

docs-website/docs/pipeline-components/builders/promptbuilder.mdx

@@ -188,6 +188,45 @@ result = p.run({"prompt_builder": {"documents": documents, "query": question}})
 print(result)
 ```
 
+#### In YAML
+
+This is the YAML representation of the RAG pipeline shown above. It renders a custom prompt template by filling it with the contents of retrieved documents and a query, then sends the rendered prompt to a generator.
+
+```yaml
+components:
+  llm:
+    init_parameters:
+      api_base_url: null
+      api_key:
+        env_vars:
+        - OPENAI_API_KEY
+        strict: true
+        type: env_var
+      generation_kwargs: {}
+      http_client_kwargs: null
+      max_retries: null
+      model: gpt-5-mini
+      organization: null
+      streaming_callback: null
+      system_prompt: null
+      timeout: null
+    type: haystack.components.generators.openai.OpenAIGenerator
+  prompt_builder:
+    init_parameters:
+      required_variables: null
+      template: "\n    Given these documents, answer the question.\\nDocuments:\n\
+        \    {% for doc in documents %}\n        {{ doc.content }}\n    {% endfor\
+        \ %}\n\n    \\nQuestion: {{query}}\n    \\nAnswer:\n    "
+      variables: null
+    type: haystack.components.builders.prompt_builder.PromptBuilder
+connection_type_validation: true
+connections:
+- receiver: llm.prompt
+  sender: prompt_builder.prompt
+max_runs_per_component: 100
+metadata: {}
+```
+
 #### Changing the template at runtime (Prompt Engineering)
 
 `PromptBuilder` allows you to switch the prompt template of an existing pipeline. The example below builds on top of the existing pipeline in the previous section. We are invoking the existing pipeline with a new prompt template:
@@ -257,6 +296,45 @@ p.run(
 Note that `language_template` introduces `answer_language` variable which is not bound to any pipeline variable. If not set otherwise, it would use its default value, "English". In this example, we overwrite its value to "German".
 The `template_variables` allows you to overwrite pipeline variables (such as documents) as well.
 
+### In YAML
+
+This is the YAML representation of the RAG pipeline shown above. It renders a custom prompt template by filling it with the contents of retrieved documents and a query, then sends the rendered prompt to a generator.
+
+```yaml
+components:
+  llm:
+    init_parameters:
+      api_base_url: null
+      api_key:
+        env_vars:
+        - OPENAI_API_KEY
+        strict: true
+        type: env_var
+      generation_kwargs: {}
+      http_client_kwargs: null
+      max_retries: null
+      model: gpt-5-mini
+      organization: null
+      streaming_callback: null
+      system_prompt: null
+      timeout: null
+    type: haystack.components.generators.openai.OpenAIGenerator
+  prompt_builder:
+    init_parameters:
+      required_variables: null
+      template: "\n    Given these documents, answer the question.\\nDocuments:\n\
+        \    {% for doc in documents %}\n        {{ doc.content }}\n    {% endfor\
+        \ %}\n\n    \\nQuestion: {{query}}\n    \\nAnswer:\n    "
+      variables: null
+    type: haystack.components.builders.prompt_builder.PromptBuilder
+connection_type_validation: true
+connections:
+- receiver: llm.prompt
+  sender: prompt_builder.prompt
+max_runs_per_component: 100
+metadata: {}
+```
+
 ## Additional References
 
 🧑‍🍳 Cookbooks: