Add E2E coverage for profile delegate source

[Yuandi (DDKinger)]

Summary

Adds test/e2e/tests/Feature.DelegateSource.Tests.ps1 covering PR #488's strict delegate source routing — the direct counterpart to #486 for #481.

#488 is now merged, so this branch is rebased onto main and its diff is test-only.

Cases (environment-gated: needs a runnable default WSL distro)

1. An explicit WSL delegate source never falls back to the Windows host — the regression Add profile-scoped command palette agents #488 fixes. A random never-installed agent name deterministically forces the "agent unavailable in WSL" branch; the pane must show bash's own not found.
2. The default delegate source is never diverted to WSL — guards the removed active-pane WSL inference; the pane must show the real Windows spawn failure.

TerminalPage.cpp's profile resolution (commandPaletteAgent → --delegate-source/--delegate-wsl-distro) is only reachable via non-injectable UI (Alt+Shift+B, the Alt+Shift+/ palette, ?<prompt>), so — exactly like Feature.Delegate — these cases drive the delegate engine directly with the flags it now always passes.

Validation

• Post-merge main build → both cases pass; Invoke-ItE2EReport.ps1 -UpdateReport credits C245 as [x], C244 stays manual.
• Pre-fix proof: run against a wta.exe built before Add profile-scoped command palette agents #488 (no --delegate-source flag), case 1 fails with AUTOMATION FAILED rather than passing vacuously — confirmed twice, once deliberately on a main-built binary and once accidentally against a stale deployment.

Checklist

New Profile command palette agent section in doc/release-check-list.md, mirroring #481's entries:

• C244 Profile Command palette agent picker works — manual (picker UI isn't harness-drivable, same rationale as C237).
• C245 Command palette agent source is strict — mapped to this suite in release-coverage-map.psd1.

The --delegate-source argument-validation branches (parse_delegate_source, require_delegate_agent_for_explicit_source) are already covered by cli/delegate.rs's own unit tests, so they are not duplicated here.

[Copilot]

Pull request overview

This PR extends the profile-scoped delegation work from PR #488 by wiring the new commandPaletteAgent profile setting through the SettingsModel + Settings UI, updating wta delegate to accept explicit --delegate-source/--delegate-wsl-distro, and adding an end-to-end ItE2E suite to validate strict host/WSL routing behavior at the WT↔WTA boundary.

Changes:

• Add explicit delegate source selection to wta delegate (--delegate-source host|wsl + --delegate-wsl-distro) and make host/WSL launchability checks source-strict (no auto-routing/fallback).
• Add profile setting plumbing for commandPaletteAgent (settings model, schema, UI pickers, and TerminalPage delegation commandline construction).
• Add a new ItE2E suite (Feature.DelegateSource.Tests.ps1) and map it into release coverage documentation.

Reviewed changes

Copilot reviewed 34 out of 34 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
tools/wta/src/cli/mod.rs	Pass new delegate source/distro args through CLI dispatch into delegate runner.
tools/wta/src/cli/delegate.rs	Implement parsing/validation for delegate source flags; enforce source-strict launchability; add WSL cwd selection + unit tests.
tools/wta/src/cli/args.rs	Add clap flags --delegate-source and --delegate-wsl-distro to the delegate subcommand.
tools/wta/src/cli_tests.rs	Update CLI parsing tests and adjust comments to reflect delegate no longer uses active-pane WSL inference.
test/e2e/tests/Feature.DelegateSource.Tests.ps1	New ItE2E coverage for strict host/WSL delegation routing behavior.
test/e2e/release-coverage-map.psd1	Map new checklist item (“Command palette agent source is strict”) to the new E2E suite.
test/e2e/README.md	Update suite table and coverage counts to include the new delegate-source suite.
src/cascadia/UnitTests_SettingsModel/ProfileTests.cpp	Extend profile inheritance/clear tests to cover commandPaletteAgent.
src/cascadia/TerminalSettingsModel/Profile.idl	Add inheritable CommandPaletteAgent profile setting.
src/cascadia/TerminalSettingsModel/MTSMSettings.h	Add commandPaletteAgent to the settings X-macro list.
src/cascadia/TerminalSettingsEditor/Resources/en-US/Resources.resw	Add localized strings for the new profile “Command palette agent” setting.
src/cascadia/TerminalSettingsEditor/Resources/de-DE/Resources.resw	Same: localized strings.
src/cascadia/TerminalSettingsEditor/Resources/es-ES/Resources.resw	Same: localized strings.
src/cascadia/TerminalSettingsEditor/Resources/fr-FR/Resources.resw	Same: localized strings.
src/cascadia/TerminalSettingsEditor/Resources/it-IT/Resources.resw	Same: localized strings.
src/cascadia/TerminalSettingsEditor/Resources/ja-JP/Resources.resw	Same: localized strings.
src/cascadia/TerminalSettingsEditor/Resources/ko-KR/Resources.resw	Same: localized strings.
src/cascadia/TerminalSettingsEditor/Resources/pt-BR/Resources.resw	Same: localized strings.
src/cascadia/TerminalSettingsEditor/Resources/ru-RU/Resources.resw	Same: localized strings.
src/cascadia/TerminalSettingsEditor/Resources/sr-Cyrl-RS/Resources.resw	Same: localized strings.
src/cascadia/TerminalSettingsEditor/Resources/uk-UA/Resources.resw	Same: localized strings.
src/cascadia/TerminalSettingsEditor/Resources/zh-CN/Resources.resw	Same: localized strings.
src/cascadia/TerminalSettingsEditor/Resources/zh-TW/Resources.resw	Same: localized strings.
src/cascadia/TerminalSettingsEditor/Resources/qps-ploc/Resources.resw	Same: pseudo-locale strings.
src/cascadia/TerminalSettingsEditor/Resources/qps-ploca/Resources.resw	Same: pseudo-locale strings.
src/cascadia/TerminalSettingsEditor/Resources/qps-plocm/Resources.resw	Same: pseudo-locale strings.
src/cascadia/TerminalSettingsEditor/ProfileViewModel.idl	Add VM properties for command palette agent list + selection and projected setting.
src/cascadia/TerminalSettingsEditor/ProfileViewModel.h	Add VM accessors and list member for command palette agent entries; refactor list rebuild entry point.
src/cascadia/TerminalSettingsEditor/ProfileViewModel.cpp	Build/display entries for both agent-pane backend and command palette agents; keep global-vs-profile selection behavior consistent.
src/cascadia/TerminalSettingsEditor/Profiles_Base.xaml	Add UI setting container + ComboBox for per-profile Command palette agent selection.
src/cascadia/TerminalApp/TerminalPage.cpp	Resolve profile commandPaletteAgent into explicit wta delegate flags and enforce “fail closed” for unknown/blocked profile selections.
README.md	Document the new per-profile command palette agent behavior and strictness.
doc/release-check-list.md	Add new checklist section/items for profile command palette agent selection and strict routing.
doc/cascadia/profiles.schema.json	Add commandPaletteAgent to profile JSON schema with the same host/wsl encoding constraints as agent-pane backend.

Suppressed comments (2)

test/e2e/tests/Feature.DelegateSource.Tests.ps1:79

• The helper hardcodes a delegate agent that is guaranteed to be missing in WSL. That makes the "default source is never diverted to WSL" case unable to detect a regression where WTA routes to WSL when the delegate agent is available in-distro (the historical inference path). Allow the helper to take a delegate-agent override so the host-default test can pick a command that’s present in WSL but not on Windows (e.g. /bin/sh).

            param([string[]]$ExtraArgs = @())

test/e2e/tests/Feature.DelegateSource.Tests.ps1:122

• To prove the default source isn't auto-routed into WSL, the delegate agent should be something that would be available in WSL (so a regression could route there) but is not launchable on the Windows host. Using a bogus agent here is absent everywhere, so it can’t distinguish host-vs-WSL routing.

        $d = & $script:RunDelegate

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated no new comments.

Suppressed comments (3)

test/e2e/tests/Feature.DelegateSource.Tests.ps1:20

• This suite invokes wta delegate with --agent 'copilot --acp --stdio' and configures acpAgent/delegateAgent to copilot, but the discovery gate doesn’t check that the copilot CLI is installed. On machines with WSL+winapp but no Copilot CLI, this will run and then fail (unlike Feature.Delegate.Tests.ps1, which gates on Get-Command copilot).

    $script:Ready = [bool](
        (Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' }) -and
        (Get-Command winapp -ErrorAction SilentlyContinue) -and
        (Get-Command wsl.exe -ErrorAction SilentlyContinue)
    )

test/e2e/tests/Feature.DelegateSource.Tests.ps1:36

• When the default WSL distro probe fails, BeforeAll sets $script:skipReason but still starts the Terminal process. Since both It blocks immediately skip when $script:skipReason is set, returning early here avoids unnecessary app startup work (and reduces noise/flakiness in environment-gated runs).

        if ($distroProbe.ExitCode -ne 0 -or -not $script:distro) {
            $script:skipReason = 'no runnable default WSL distro is available'
        }

test/e2e/tests/Feature.DelegateSource.Tests.ps1:39

• Similarly, when the default distro name contains characters that can’t be safely represented on the command line, the suite sets $script:skipReason but continues into app startup. Returning early keeps this environment-gate cheap and consistent with Feature.WslAgentBackend.Tests.ps1.

        elseif ($script:distro -match '["\r\n]') {
            $script:skipReason = 'the default WSL distro name cannot be represented safely in a test command line'
        }