fix(cli): avoid encoded PowerShell commands

[marius-kilocode]

Windows endpoint security tools commonly treat powershell.exe -EncodedCommand <base64> as obfuscated command execution. Kilo started using that transport to avoid Windows PowerShell mojibake, but the command-line shape is indistinguishable from a common AV and EDR heuristic even when the decoded command is benign.

This keeps the Windows PowerShell UTF-8 setup from #11148 while making the executed command visible to PowerShell as plaintext via -Command. The wrapper still sets console input, console output, and `` to UTF-8 before running the approved command, so the Unicode behavior added for localized Windows output remains in place without the nested Base64 decode and ScriptBlock.Create path.

The result is a less suspicious process command line for Windows users and security tooling while preserving the intended PowerShell 5.1 and PowerShell 7 invocation shape.

[kilo-code-bot]

Code Review Summary

Status: No Issues Found | Recommendation: Merge

Files Reviewed (2 files)

• packages/opencode/src/kilocode/shell/shell.ts
• packages/opencode/test/kilocode/shell/shell.test.ts

Previous Review Summaries (2 snapshots, latest commit e95384d)

Current summary above is authoritative. Previous snapshots are kept for context only.

Previous review (commit e95384d)

Status: 1 Issues Found | Recommendation: Address before merge

Overview

Severity	Count
CRITICAL	0
WARNING	1
SUGGESTION	0

Issue Details (click to expand)

WARNING

File	Line	Issue
packages/opencode/src/kilocode/shell/shell.ts	21	The new prologue parser still misses legal script prologues like [CmdletBinding()] and <# ... #> comments before param(...), so the UTF-8 setup can still invalidate advanced scripts.

Files Reviewed (2 files)

• packages/opencode/src/kilocode/shell/shell.ts - 1 issue
• packages/opencode/test/kilocode/shell/shell.test.ts - 0 issues

Fix these issues in Kilo Cloud

Previous review (commit 579a787)

Status: 1 Issues Found | Recommendation: Address before merge

Overview

Severity	Count
CRITICAL	0
WARNING	1
SUGGESTION	0

Issue Details (click to expand)

WARNING

File	Line	Issue
packages/opencode/src/kilocode/shell/shell.ts	9	Appending the payload after the UTF-8 prelude breaks script-level PowerShell constructs like param, using, and #requires that must be the first statement.

Files Reviewed (5 files)

• .changeset/calm-powershell-alerts.md - 0 issues
• packages/opencode/src/kilocode/shell/shell.ts - 1 issue
• packages/opencode/src/shell/shell.ts - 0 issues
• packages/opencode/src/tool/shell.ts - 0 issues
• packages/opencode/test/kilocode/shell/shell.test.ts - 0 issues

Fix these issues in Kilo Cloud

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_{Reviewed by gpt-5.4-20260305 · Input: 45.3K · Output: 5.5K · Cached: 78.3K}

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