Propagate --explain flag into interactive mode

[Copilot]

--explain was wired up for single-shot mode but silently ignored in interactive mode: interactive.Run had no explain parameter, replBuildSystemPrompt hardcoded false, and handleResponse passed false to executor.Run.

Changes

• internal/interactive/repl.go: Add explain bool to Run, replBuildSystemPrompt, and handleResponse; thread it through to llm.BuildSystemPrompt and executor.Run
• cmd/root.go: Pass explainFlag to interactiveRun in the interactive branch
• Tests: Update all stubs and call sites to match new signatures; add TestRunRoot_InteractiveMode_ExplainFlag to verify explainFlag is forwarded correctly (both true and false) to interactiveRun; add TestRun_ExplainFlagPropagated to verify explain=true reaches both replBuildSystemPrompt and replHandleResponse inside the REPL loop

// Before
replBuildSystemPrompt = func(osName, shellName, shellVersion, cwd string) string {
    return llm.BuildSystemPrompt(osName, shellName, shellVersion, cwd, false) // hardcoded
}
return executor.Run(resp.Commands, cfg, shellInfo, false) // hardcoded

// After
replBuildSystemPrompt = func(osName, shellName, shellVersion, cwd string, explain bool) string {
    return llm.BuildSystemPrompt(osName, shellName, shellVersion, cwd, explain)
}
return executor.Run(resp.Commands, cfg, shellInfo, explain)

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[Copilot]

Pull request overview

Fixes interactive mode ignoring the --explain flag by threading the flag through the interactive REPL entrypoint and down into system-prompt construction and command execution, matching single-shot behavior.

Changes:

• Add an explain bool parameter to interactive.Run, replBuildSystemPrompt, and handleResponse, and pass it through to llm.BuildSystemPrompt and executor.Run.
• Update the interactive branch in cmd/root.go to pass explainFlag into interactiveRun.
• Update impacted tests/stubs to match the new function signatures.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
internal/interactive/repl.go	Threads explain through the interactive REPL prompt builder and response handling into executor.Run.
cmd/root.go	Forwards the Cobra --explain flag into interactive mode via interactiveRun(..., explainFlag).
internal/interactive/repl_test.go	Updates handleResponse callsites to include the new explain argument.
internal/interactive/repl_run_test.go	Updates REPL hook stubs to match new signatures (prompt builder / response handler).
cmd/root_test.go	Updates interactive-mode stubs for interactiveRun to accept the new explain argument.

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[Copilot]

Interactive mode tests stub interactiveRun but never assert that the new explain flag is forwarded. Add/extend a test to set explainFlag=true before runRoot and verify the stub receives explain=true (and similarly verify false by default) so this regression can’t reappear.

[Copilot]

Added TestRunRoot_InteractiveMode_ExplainFlag in commit 8818e5a. It calls runRoot with explainFlag=false and verifies the stub receives false, then again with explainFlag=true and verifies it receives true.

[Copilot]

This test updates the replBuildSystemPrompt signature to accept explain, but it still always calls Run(..., false) and doesn’t assert what explain value was passed into the prompt builder/response handler. Add a case that runs with explain=true and asserts the captured explain argument(s) so interactive mode explain propagation is covered.

[Copilot]

Added TestRun_ExplainFlagPropagated in commit 8818e5a. It calls Run(..., true) and asserts that both replBuildSystemPrompt and replHandleResponse receive explain=true.

[kriserickson]

@copilot fix the tests for this biuld.

[Copilot]

@copilot fix the tests for this biuld.

Done in commit 8818e5a. Added the two tests requested by the reviewer to assert explain flag propagation into interactive mode.