Show automatic unsandbox retries in the chat terminal UI

[dileepyavan]

Summary

• add automatic retry detection for sandbox-blocked foreground terminal executions
• show the unsandboxed retry as a terminal tool invocation in chat after the user clicks Allow Once
• refactor command rewriting into a reusable helper and add retry coverage tests

Details

When a sandboxed runInTerminal execution fails with output that looks blocked by the sandbox, the tool now:

• prompts the user with the existing Allow Once flow
• if accepted, emits a new terminal invocation part in chat for the unsandboxed retry
• runs the retry outside the sandbox and updates that chat terminal part when the retry completes
• prepends a note to the final tool result explaining that the command was retried outside the sandbox

This keeps the retry visible in chat in the same style as normal terminal tool executions instead of only switching execution behavior behind the scenes.

Testing

• node ./node_modules/eslint/bin/eslint.js src/vs/workbench/contrib/terminalContrib/chatAgentTools/browser/tools/runInTerminalTool.ts
• ./scripts/test.sh --run src/vs/workbench/contrib/terminalContrib/chatAgentTools/test/electron-browser/runInTerminalTool.test.ts

Fixes #308506

[Copilot]

Pull request overview

This PR adds client-side detection of “sandbox blocked” failures for runInTerminal and, after user consent, surfaces the unsandboxed retry as a separate terminal tool invocation in chat so the retry is visible in the transcript.

Changes:

• Detect sandbox-blocked failures from command output and offer an Allow Once unsandboxed retry without a model roundtrip.
• Emit an additional chat tool invocation part representing the unsandboxed retry, and prepend a note to the final tool result.
• Refactor command rewriting into a reusable helper and add predicate-level retry detection tests.

Show a summary per file

File	Description
src/vs/workbench/contrib/terminalContrib/chatAgentTools/browser/tools/runInTerminalTool.ts	Adds auto unsandbox retry detection/confirmation + external tool invocation update emission; refactors command rewriting.
src/vs/workbench/contrib/terminalContrib/chatAgentTools/test/electron-browser/runInTerminalTool.test.ts	Adds unit tests for shouldAutomaticallyRetryUnsandboxed.

Copilot's findings

• Files reviewed: 2/2 changed files
• Comments generated: 3