Add changelog for 2025-05-14 (#399)

Author: quantstruct-bot

fern/changelog/2025-05-13.mdx

@@ -0,0 +1,10 @@
+# GoHighLevel Tools for Calendar and Contact Management
+
+You can now use new [GoHighLevel tools](https://www.gohighlevel.com) in all models, templates, and workflows directly through the [`/tool`](https://api.vapi.ai/api#:~:text=/tool) and [`/tool/{id}`](https://api.vapi.ai/api#:~:text=/tool/%7Bid%7D) endpoints with the following capabilities:
+   - **Contact Management**:
+     - [GoHighLevelContactGetTool](https://api.vapi.ai/api#:~:text=GoHighLevelContactGetTool): Fetch contact information from GoHighLevel
+     - [GoHighLevelContactCreateTool](https://api.vapi.ai/api#:~:text=GoHighLevelContactCreateTool): Create new contacts in GoHighLevel
+
+   - **Calendar Management**:
+     - [GoHighLevelCalendarEventCreateTool](https://api.vapi.ai/api#:~:text=GoHighLevelCalendarEventCreateTool): Schedule new calendar events programmatically
+     - [GoHighLevelCalendarAvailabilityTool](https://api.vapi.ai/api#:~:text=GoHighLevelCalendarAvailabilityTool): Check calendar availability for scheduling

fern/changelog/2025-05-14.mdx

@@ -0,0 +1,20 @@
+1. **Specify Start Node in Workflows with `isStart` Property**: You can now explicitly define the starting point of your workflow by setting the `isStart` property to `true` on any node like [`Say`](https://api.vapi.ai/api#:~:text=Say), [`Gather`](https://api.vapi.ai/api#:~:text=Gather), or [`Hangup`](https://api.vapi.ai/api#:~:text=Hangup).
+
+2. **Updated Model Options in `GroqModel`**: You can now use the following new Assistant modles with [Groq](https://api.vapi.ai/api#:~:text=GroqModel):
+   - `meta-llama/llama-4-maverick-17b-128e-instruct`
+   - `meta-llama/llama-4-scout-17b-16e-instruct`
+   - `mistral-saba-24b`
+   - `compound-beta`
+   - `compound-beta-mini`
+
+<Frame caption="New Groq Models">
+    <img src="../static/images/changelog/new-groq-models.png" alt="New Groq Models" />
+</Frame>
+
+<Warning>Note that some older models have been removed, including `llama-3.1-70b-versatile` and `mixtral-8x7b-32768`.</Warning>
+
+3. **New `Kylie` Voice Available in Vapi**: You can now use the new `Kylie` voice when using [`Vapi` as your voice provider](https://dashboard.vapi.ai/assistants#:~:text=Voice%20Configuration). You can learn more in the [Vapi voices documentation](https://docs.vapi.ai/providers/voice/vapi-voicesn).
+
+<Frame caption="New Vapi Voice: Kylie">
+    <img src="../static/images/changelog/vapi-voice-kylie.png" alt="New Kylie Voice" />
+</Frame>