[Bug] Input Templates appear after each message

### Bug Description

The input template should NOT be visible to the user, and should essentially act as a 'local' system message for that active conversation. As of the latest build, the input template is visually injected into every message the user sends.

### Steps to Reproduce

1. Enter an input template:
``` Act as a virtual assistant powered by model: '{{model}}', now time is {{time}}, response in {{lang}} lang, my input is:'''{{input}}''' ```
2. Write a message in the chatbox
3. Watch as the input template message is clearly visibly after every sent message.

### Expected Behavior

The input template message should not show up for the user, just like the global system message does not get visually injected into the user's messages.

### Screenshots


### Deployment Method

- [ ] Docker
- [ ] Vercel
- [X] Server

### Desktop OS

Win10

### Desktop Browser

Chrome

### Desktop Browser Version

_No response_

### Smartphone Device

_No response_

### Smartphone OS

_No response_

### Smartphone Browser

_No response_

### Smartphone Browser Version

_No response_

### Additional Logs

_No response_