fix(vscode): preserve Explorer after window reload

[lambertjosh]

Summary

• stop treating hidden Kilo view state as closed primary-sidebar state
• let VS Code restore Explorer and other primary sidebar views without Kilo closing them after activation
• add a regression guard while preserving Kilo's live visibility context and stream handling

Kilo previously persisted WebviewView.visible as sidebar state, then ran the global workbench.action.closeSidebar command during startup when Kilo itself was hidden. This closed Explorer shortly after a window reload even though the primary sidebar was meant to remain open.

Before

f7f7bbf.mp4

After

Screen.Recording.2026-06-05.at.10.29.14.AM.mov

[lambertjosh]

Reported originally in discord: https://discord.com/channels/1349288496988160052/1458112753687593096/1512291344515727450

[kilo-code-bot]

Code Review Summary

Status: 1 Issue Found | Recommendation: Address before merge

Overview

Severity	Count
CRITICAL	0
WARNING	1
SUGGESTION	0

Issue Details (click to expand)

WARNING

File	Line	Issue
packages/kilo-vscode/tests/unit/extension-arch.test.ts	—	Regression guard mentioned in PR description is absent from final state

Other Observations (not in diff)

Missing regression test (PR description vs. actual state):

The PR description says "add a regression guard while preserving Kilo's live visibility context and stream handling". Commit 54534bd adds the guard (an "Extension — sidebar visibility" describe block in extension-arch.test.ts), but commit ca5c4d9 then removes it, leaving the final PR with no regression test at all. The test file is net-unchanged from main.

The guard is meaningful — it enforces workbench.action.closeSidebar and onSidebarVisibilityChange don't reappear in the codebase, which is exactly the kind of regression that originally caused this bug. Consider re-adding the test from 54534bd (or keeping a stripped version without the KILO_PROVIDER_OPTIONS_FILE reference if that was the only issue).

Stale workspaceState key (benign):

Existing users who had { sidebar: false } written to workspaceState under RESTORE_KEY by the old code will retain that stale key. The new RestoreState type simply ignores unknown keys so this is harmless, but a one-time cleanup (context.workspaceState.update(RESTORE_KEY, { agentManager: restore.agentManager })) would be hygienic. Not blocking.

Files Reviewed (4 files)

• .changeset/steady-sidebar-reload.md — changeset looks correct, user-facing description is clear
• packages/kilo-vscode/src/KiloProvider.ts — onSidebarVisibilityChange call removed cleanly; setStreamVisibility and sidebarVisible context key are preserved
• packages/kilo-vscode/src/extension.ts — closeSidebar logic and sidebar field removed cleanly from RestoreState; agentManager restore path is unaffected
• packages/kilo-vscode/src/kilo-provider/options.ts — onSidebarVisibilityChange option removed

Fix these issues in Kilo Cloud

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_{Reviewed by claude-4.6-sonnet-20260217 · 913,417 tokens}

_{Review guidance: REVIEW.md from base branch main}