macOS: terminal window hangs with screen-reader support enabled

Does this issue occur when all extensions are disabled?: Unknown for the affected sessions. A brief synthetic terminal test with extensions disabled did not reproduce it.

- VS Code Version: 1.137.0 (645f29cc3176500b4b5762ba887cf2a7f0ffdf2c)
- OS Version: macOS 15.7.9, arm64, Apple M4 Pro, 24 GB RAM
- Installed extension (current CLI inventory): `anthropic.claude-code@2.1.273`
- Latest Insiders: not tested

Steps to Reproduce:

These are the circumstances observed in existing sessions; I don't yet have a reliable minimal reproduction.

1. Use these settings:
```json
{
"editor.accessibilitySupport": "on",
"terminal.integrated.gpuAcceleration": "off"
}
```
2. Keep several integrated terminals open running Claude Code and Codex CLI. Switching to one terminal intermittently makes the window hang.
3. During diagnosis, inspect the window's macOS accessibility tree using Codex desktop's computer-use tool. With completed Claude output visible, this was followed by another hang before any successful tab switch.

**Expected:** The window stays responsive when switching terminals or reading its accessibility state.

**Actual:** The renderer reaches about 100% CPU, while the terminal host stays mostly idle. VS Code shows “The window is not responding.” The process remains alive.

**Possible workaround:** After changing only `editor.accessibilitySupport` to `"off"` and choosing **Keep Waiting**, the existing sessions remained usable. A subsequent full accessibility-tree read took 147 ms; renderer CPU averaged 7.7% over the next 25 seconds and ended at 0.5%.

CPU had already dropped before the setting change, so this does not establish the cause or prove a permanent fix. Native process samples were captured during the hang; a DevTools CPU profile was not captured.