Make compression threshold editable in the UI. (#12317)

docs/get-started/configuration-v1.md

@@ -473,21 +473,6 @@ a few things you can try in order of recommendation:
     "loadMemoryFromIncludeDirectories": true
     ```
 
-- **`chatCompression`** (object):
-  - **Description:** Controls the settings for chat history compression, both
-    automatic and when manually invoked through the /compress command.
-  - **Properties:**
-    - **`contextPercentageThreshold`** (number): A value between 0 and 1 that
-      specifies the token threshold for compression as a percentage of the
-      model's total token limit. For example, a value of `0.6` will trigger
-      compression when the chat history exceeds 60% of the token limit.
-  - **Example:**
-    ```json
-    "chatCompression": {
-      "contextPercentageThreshold": 0.6
-    }
-    ```
-
 - **`showLineNumbers`** (boolean):
   - **Description:** Controls whether line numbers are displayed in code blocks
     in the CLI output.

docs/get-started/configuration.md

@@ -245,13 +245,13 @@ their corresponding top-level category object in your `settings.json` file.
     example `{"run_shell_command": {"tokenBudget": 2000}}`
   - **Default:** `undefined`
 
-- **`model.chatCompression.contextPercentageThreshold`** (number):
+- **`model.compressionThreshold`** (number):
   - **Description:** Sets the threshold for chat history compression as a
-    percentage of the model's total token limit. This is a value between 0 and 1
+    fraction of the model's total token limit. This is a value between 0 and 1
     that applies to both automatic compression and the manual `/compress`
     command. For example, a value of `0.6` will trigger compression when the
     chat history exceeds 60% of the token limit.
-  - **Default:** `0.7`
+  - **Default:** `0.2`
 
 - **`model.skipNextSpeakerCheck`** (boolean):
   - **Description:** Skip the next speaker check.