bug: fs_write failing on paths with "~"

### 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

### Expected behaviour

The `fs_write` tool correctly displays the diff requested by the model to accept or deny.

### Actual behaviour

`fs_write` returns the error:

```
Amazon Q is having trouble responding right now:
0: failed to print tool, `fs_write`: No such file or directory (os error 2)

Location:
crates/chat-cli/src/cli/chat/mod.rs:1007

Backtrace omitted. Run with RUST_BACKTRACE=1 environment variable to display it.
Run with RUST_BACKTRACE=full to include source snippets.
```

when it tries to display the diff generated by the model. I ran `q chat -vvv` and saw that the model returned valid-looking output so I expect it's something client-side with how the tool call is being processed.

### Steps to reproduce

Here's the chat log, I repeated this with a couple different files in my home directory and they all behaved the same when I used `~/` in the path.

```
$ q chat
⚠ amzn_mcp has the following warning:
The following tool names are changed:
- amzn_mcp___slack-send-message -> amzn_mcp___slacksendmessage
✓ 1 of 1 mcp servers initialized.

⢠⣶⣶⣦⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢀⣤⣶⣿⣿⣿⣶⣦⡀⠀
⠀⠀⠀⣾⡿⢻⣿⡆⠀⠀⠀⢀⣄⡄⢀⣠⣤⣤⡀⢀⣠⣤⣤⡀⠀⠀⢀⣠⣤⣤⣤⣄⠀⠀⢀⣤⣤⣤⣤⣤⣤⡀⠀⠀⣀⣤⣤⣤⣀⠀⠀⠀⢠⣤⡀⣀⣤⣤⣄⡀⠀⠀⠀⠀⠀⠀⢠⣿⣿⠋⠀⠀⠀⠙⣿⣿⡆
⠀⠀⣼⣿⠇⠀⣿⣿⡄⠀⠀⢸⣿⣿⠛⠉⠻⣿⣿⠛⠉⠛⣿⣿⠀⠀⠘⠛⠉⠉⠻⣿⣧⠀⠈⠛⠛⠛⣻⣿⡿⠀⢀⣾⣿⠛⠉⠻⣿⣷⡀⠀⢸⣿⡟⠛⠉⢻⣿⣷⠀⠀⠀⠀⠀⠀⣼⣿⡏⠀⠀⠀⠀⠀⢸⣿⣿
⠀⢰⣿⣿⣤⣤⣼⣿⣷⠀⠀⢸⣿⣿⠀⠀⠀⣿⣿⠀⠀⠀⣿⣿⠀⠀⢀⣴⣶⣶⣶⣿⣿⠀⠀⠀⣠⣾⡿⠋⠀⠀⢸⣿⣿⠀⠀⠀⣿⣿⡇⠀⢸⣿⡇⠀⠀⢸⣿⣿⠀⠀⠀⠀⠀⠀⢹⣿⣇⠀⠀⠀⠀⠀⢸⣿⡿
⢀⣿⣿⠋⠉⠉⠉⢻⣿⣇⠀⢸⣿⣿⠀⠀⠀⣿⣿⠀⠀⠀⣿⣿⠀⠀⣿⣿⡀⠀⣠⣿⣿⠀⢀⣴⣿⣋⣀⣀⣀⡀⠘⣿⣿⣄⣀⣠⣿⣿⠃⠀⢸⣿⡇⠀⠀⢸⣿⣿⠀⠀⠀⠀⠀⠀⠈⢿⣿⣦⣀⣀⣀⣴⣿⡿⠃
⠚⠛⠋⠀⠀⠀⠀⠘⠛⠛⠀⠘⠛⠛⠀⠀⠀⠛⠛⠀⠀⠀⠛⠛⠀⠀⠙⠻⠿⠟⠋⠛⠛⠀⠘⠛⠛⠛⠛⠛⠛⠃⠀⠈⠛⠿⠿⠿⠛⠁⠀⠀⠘⠛⠃⠀⠀⠘⠛⠛⠀⠀⠀⠀⠀⠀⠀⠀⠙⠛⠿⢿⣿⣿⣋⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠈⠛⠿⢿⡧

╭─────────────────────────────── Did you know? ────────────────────────────────╮
│ │
│ You can resume the last conversation from your current directory by │
│ launching with q chat --resume │
│ │
╰──────────────────────────────────────────────────────────────────────────────╯

/help all commands • ctrl + j new lines • ctrl + s fuzzy search
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
> Write an appropriate header comment on my file ~/karakuri-checkstyle.xml
I'll help you write an appropriate header comment for your karakuri-checkstyle.xml file. Let me
first check if the file exists and what it contains.

🛠️ Using tool: fs_read (trusted)
⋮
● Reading file: ~/karakuri-checkstyle.xml, all lines
⋮
● Completed in 0.0s

Now I'll create an appropriate header comment for your karakuri-checkstyle.xml file:

🛠️ Using tool: fs_write
⋮
● Path: ~/karakuri-checkstyle.xml

Amazon Q is having trouble responding right now:
0: failed to print tool, `fs_write`: No such file or directory (os error 2)

Location:
crates/chat-cli/src/cli/chat/mod.rs:1007

Backtrace omitted. Run with RUST_BACKTRACE=1 environment variable to display it.
Run with RUST_BACKTRACE=full to include source snippets.
> Try again, it's in your local directory
I'll try again with the correct path. Let me check if the file exists in my current directory.

🛠️ Using tool: fs_read (trusted)
⋮
● Reading file: /Users/mukhanee/karakuri-checkstyle.xml, all lines
⋮
● Completed in 0.0s

🛠️ Using tool: fs_write
⋮
● Path: karakuri-checkstyle.xml

1, 1:
2, 2:
5, 5:
6, 6:

Allow this action? Use 't' to trust (always allow) this tool for the session. [y/n/t]:

> /quit
```

### Environment

```yaml
$ q diagnostic

[q-details]
version = "1.10.1"
hash = "cb90e381cf8391beef4b966623d913e258cbb08d"
date = "2025-05-16T13:53:39.016927Z (5d ago)"
variant = "full"

[system-info]
os = "macOS 15.4.1 (24E263)"
chip = "Apple M3 Pro"
total-cores = 12
memory = "36.00 GB"

[environment]
cwd = "/Users/USER"
cli-path = "/Users/USER"
os = "Mac"
shell-path = "/bin/zsh"
shell-version = "5.9"
terminal = "macOS"
install-method = "brew"

[env-vars]
PATH = "/Users/USER/.nvm/versions/node/v22.11.0/bin:/Users/USER/.cargo/bin:/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/.local/bin"
QTERM_SESSION_ID = "7e2008a360d5439697d85b56fe32cea0"
Q_SET_PARENT_CHECK = "1"
Q_TERM = "1.10.1"
SHELL = "/bin/zsh"
TERM = "xterm-256color"
__CFBundleIdentifier = "com.apple.Terminal"
```