refactor(ui): update knowledge graph, chunk, metadata, agent log styles (#13518)

### What problem does this PR solve?

Update UI styles:
- **Dataset** > **Knowledge graph** tooltip
- **Dataset** > **Files** > **Manage metadata** modal
- **Dataset** > **Files** > **Modify Chunking Method** > **Auto
metadata** > **Manage generation settings** modal
- **Agent** > **Canvas (Ingestion pipeline)** > **Dataflow result**

### Type of change

- [x] Refactoring

web/src/components/ui/button.tsx

@@ -86,7 +86,7 @@ const buttonVariants = cva(
 
         // Static
         // Button has no interaction transitions
-        static: '',
+        static: 'text-text-secondary',
       },
       size: {
         auto: '',