#11001: ACP: make --reset-session asynchronous and track pending resets; add PowerShell wrapper for scheduled tasks

This is the fix for issue #10693 and #10933. Optimize ACP --reset-session to be asynchronous to minimize latency for clients like Zed. - Implement pendingReset tracking in the session store. - Add PowerShell wrapper for hidden execution of scheduled tasks on Windows. - Updated documentation, changelog, and unit tests. <!-- greptile_comment --> <h2>Greptile Overview</h2> <h3>Greptile Summary</h3> - Makes ACP `--reset-session` non-blocking by starting the gateway reset in the background and deferring the await until the first `prompt()`. - Adds `pendingReset` tracking to the in-memory ACP session store/types so prompt sending can wait for completion. - Updates docs/changelog and extends unit tests for session reset behavior. - Updates Windows scheduled-task installation to generate a `.ps1` wrapper (hidden `Start-Process`) and point the task at PowerShell instead of the `.cmd` directly. <h3>Confidence Score: 3/5</h3> - This PR is close to mergeable but has a couple of runtime failure modes that should be fixed first. - Main risks are (1) a failed async session reset can permanently break prompting for that session due to an unhandled rejected pendingReset promise, and (2) the Windows scheduled task command includes a PowerShell flag that can cause task launch failures depending on the installed PowerShell/Windows variant. - src/acp/translator.ts, src/daemon/schtasks.ts <!-- greptile_other_comments_section --> _{(2/5) Greptile learns from your feedback when you react with thumbs up/down!} <!-- /greptile_comment -->