Q suddenly confused about the day of the week for current date

### Checks

- [x] I have searched [github.com/aws/amazon-q-developer-cli/issues](https://github.com/aws/amazon-q-developer-cli/issues?q=) and there are no duplicates of my issue
- [x] I have run `q doctor` in the affected terminal session
- [x] I have run `q restart` and replicated the issue again

### Operating system

macOS 15.5.0 (24F74)

### Expected behaviour

I have a prompt that I run every weekday that includes "for yesterday (or last Friday if today is Monday)". I've been running it for a few months now and it has always worked perfectly until yesterday and today where it's been confused about what day of the week it is. Did something change that's breaking Q's ability to understand what day of the week the current date is?

Expected:

```
> What is the current date (include day of week)?

> Today is Tuesday, August 19, 2025.
```

### Actual behaviour

Actual

```
> What is the current date (include day of week)?

> Today is Monday, August 19, 2025.
```

### Steps to reproduce

Open Q CLI and type "What is the current date (include day of week)?"

### Environment

```yaml

[q-details]
version = "1.14.0"
hash = "a2da6f6e4b993dd1b7a24eec967995a750e45ca7"
date = "2025-08-15T18:18:20.259882Z (4d ago)"

[system-info]
os = "macOS 15.5.0 (24F74)"
chip = "Apple M1 Pro"
total-cores = 10
memory = "32.00 GB"

[environment]
cwd = "/Users/USER"
cli-path = "/Users/USER"
install-method = "toolbox"

[env-vars]
PATH = "/Users/USER/.toolbox/bin:/opt/homebrew/bin:/usr/local/bin:/System/Cryptexes/App/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/local/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/appleinternal/bin:/Users/USER/.cargo/bin:/Applications/iTerm.app/Contents/Resources/utilities"
SHELL = "/bin/zsh"
TERM = "xterm-256color"
__CFBundleIdentifier = "com.googlecode.iterm2"
```