fix(models): ensure Tool Cody is only added when enabled (#6753)

FIX https://linear.app/sourcegraph/issue/CODY-4737

The issue was that the Tool Cody model was being added to the list of
primary models regardless of whether the feature was enabled or not. The
root cause was that the check for the existence of the Tool Cody model
was not properly scoped to the `isToolCodyEnabled` flag but was checking
the observable instead, which would always returns true as the
observable is defined.

This change fixes the issue by only adding the Tool Cody model to the
list of primary models if the `isToolCodyEnabled` flag is true and the
Tool Cody model is not already present in the list of primary models.

Included some minor clean up.

## Test plan

<!-- Required. See
https://docs-legacy.sourcegraph.com/dev/background-information/testing_principles.
-->

Verify Tool Cody is not showing up in your model dropdown if you don't
have the configuration in your settings:

<img width="603" alt="image"
src="https://github.com/user-attachments/assets/6ebdbb6e-650d-4bc4-ad62-40a285a13f5f"
/>

lib/shared/src/models/sync.ts

@@ -212,7 +212,12 @@ export function syncModels({
                                         enableToolCody
                                     ).pipe(
                                         switchMap(
-                                            ([hasEarlyAccess, hasAgenticChatFlag, defaultToHaiku]) => {
+                                            ([
+                                                hasEarlyAccess,
+                                                hasAgenticChatFlag,
+                                                defaultToHaiku,
+                                                isToolCodyEnabled,
+                                            ]) => {
                                                 // TODO(sqs): remove waitlist from localStorage when user has access
                                                 const isOnWaitlist = config.clientState.waitlist_o1
                                                 if (isDotComUser && (hasEarlyAccess || isOnWaitlist)) {
@@ -233,49 +238,57 @@ export function syncModels({
                                                         }
                                                     )
                                                 }
+
+                                                const clientModels = []
+
+                                                // Handle agentic chat features
+                                                const isAgenticChatEnabled =
+                                                    hasAgenticChatFlag ||
+                                                    (isDotComUser && !isCodyFreeUser)
                                                 const haikuModel = data.primaryModels.find(m =>
                                                     m.id.includes('5-haiku')
                                                 )
                                                 const sonnetModel = data.primaryModels.find(m =>
                                                     m.id.includes('5-sonnet')
                                                 )
-                                                // Agentic Chat is available for all Pro users.
-                                                // Enterprise users need to have the feature flag enabled.
-                                                const isAgenticChatEnabled =
-                                                    hasAgenticChatFlag ||
-                                                    (isDotComUser && !isCodyFreeUser)
-
-                                                // Requires 3.5 Haiku and 3.5 Sonnet models to be available.
+                                                const hasDeepCody = data.primaryModels.some(m =>
+                                                    m.id.includes('deep-cody')
+                                                )
                                                 if (
+                                                    !hasDeepCody &&
                                                     isAgenticChatEnabled &&
                                                     sonnetModel &&
-                                                    haikuModel &&
-                                                    // Ensure the deep-cody model is only added once.
-                                                    !data.primaryModels.some(m =>
-                                                        m.id.includes('deep-cody')
-                                                    )
+                                                    haikuModel
                                                 ) {
-                                                    const DEEPCODY_MODEL =
+                                                    clientModels.push(
                                                         getExperimentalClientModelByFeatureFlag(
                                                             FeatureFlag.DeepCody
                                                         )!
+                                                    )
+                                                }
 
-                                                    const clientModels = [DEEPCODY_MODEL]
-                                                    if (enableToolCody) {
-                                                        clientModels.push(TOOL_CODY_MODEL)
-                                                    }
+                                                const hasToolCody = data.primaryModels.some(m =>
+                                                    m.id.includes('tool-cody')
+                                                )
+                                                if (!hasToolCody && isToolCodyEnabled) {
+                                                    clientModels.push(TOOL_CODY_MODEL)
+                                                }
 
-                                                    data.primaryModels.push(
-                                                        ...maybeAdjustContextWindows(clientModels).map(
-                                                            createModelFromServerModel
-                                                        )
+                                                // Add the client models to the list of models.
+                                                data.primaryModels.push(
+                                                    ...maybeAdjustContextWindows(clientModels).map(
+                                                        createModelFromServerModel
                                                     )
-                                                }
-                                                // set the default model to Haiku for free users
-                                                if (isDotComUser && isCodyFreeUser && defaultToHaiku) {
-                                                    if (haikuModel) {
-                                                        data.preferences!.defaults.chat = haikuModel.id
-                                                    }
+                                                )
+
+                                                // Set the default model to Haiku for free users.
+                                                if (
+                                                    isDotComUser &&
+                                                    isCodyFreeUser &&
+                                                    defaultToHaiku &&
+                                                    haikuModel
+                                                ) {
+                                                    data.preferences!.defaults.chat = haikuModel.id
                                                 }
 
                                                 return Observable.of(data)