docs: Update README and CHANGELOG after v1.4.257

CHANGELOG.md

@@ -1,5 +1,15 @@
 # Changelog
 
+## v1.4.257 (2025-07-17)
+
+### PR [#1628](https://github.com/danielmiessler/Fabric/pull/1628) by [ksylvan](https://github.com/ksylvan): Introduce CLI Flag to Disable OpenAI Responses API
+
+- Add `--disable-responses-api` CLI flag for OpenAI control and llama-server compatibility
+- Implement `SetResponsesAPIEnabled` method in OpenAI client with configuration control
+- Update default config path to `~/.config/fabric/config.yaml`
+- Add CLI completions for new API flag across zsh, bash, and fish shells
+- Update CHANGELOG after v1.4.256 release
+
 ## v1.4.256 (2025-07-17)
 
 ### PR [#1624](https://github.com/danielmiessler/Fabric/pull/1624) by [ksylvan](https://github.com/ksylvan): Feature: Add Automatic ~/.fabric.yaml Config Detection

README.md

@@ -544,10 +544,13 @@ Application Options:
       --image-compression=          Compression level 0-100 for JPEG/WebP formats (default: not set)
       --image-background=           Background type: opaque, transparent (default: opaque, only for
                                     PNG/WebP)
+      --suppress-think              Suppress text enclosed in thinking tags
+      --think-start-tag=            Start tag for thinking sections (default: <think>)
+      --think-end-tag=              End tag for thinking sections (default: </think>)
+      --disable-responses-api       Disable OpenAI Responses API (default: false)
 
 Help Options:
   -h, --help                        Show this help message
-
 ```
 
 ## Our approach to prompting