Fix: The Context Generator(Transformer) node can only be followed by a Tokenizer(Indexer) and a Context Generator(Transformer). #9869 (#10515)

### What problem does this PR solve?

Fix: The Context Generator node can only be followed by a Tokenizer and
a Context Generator. #9869
### Type of change


- [x] New Feature (non-breaking change which adds functionality)

web/src/locales/en.ts

@@ -1703,8 +1703,8 @@ This delimiter is used to split the input text into several text pieces echo of
       parser: 'Parser',
       parserDescription:
         'Extracts raw text and structure from files for downstream processing.',
-      tokenizer: 'Tokenizer',
-      tokenizerRequired: 'Please add the Tokenizer node first',
+      tokenizer: 'Indexer',
+      tokenizerRequired: 'Please add the Indexer node first',
       tokenizerDescription:
         'Transforms text into the required data structure (e.g., vector embeddings for Embedding Search) depending on the chosen search method.',
       splitter: 'Token Splitter',
@@ -1713,7 +1713,7 @@ This delimiter is used to split the input text into several text pieces echo of
       hierarchicalMergerDescription:
         'Split documents into sections by title hierarchy with regex rules for finer control.',
       hierarchicalMerger: 'Title Splitter',
-      extractor: 'Context Generator',
+      extractor: 'Transformer',
       extractorDescription:
         'Use an LLM to extract structured insights from document chunks—such as summaries, classifications, etc.',
       outputFormat: 'Output format',