fix(opencode): handle literal Windows archive paths - #43038

AI code review — automated review for reference; please use your judgment.

1. packages/opencode/src/util/archive.ts:6 — solid fix: routing the paths through $env: removes both the single-quote injection hole (a path like x'; Remove-Item ...) and the wildcard/globbing misparse that motivated this ([copy] under non-literal -Path). Consider also asserting in Process.run's contract (or a comment here) that env merges with process.env — if it ever switches to replace-semantics, PowerShell on Windows can fail to start without SystemRoot, and this call site would be the reason.

2. packages/opencode/src/util/archive.ts:9 — with paths no longer embedded in the command string, failures now log a command that contains only $env:... placeholders, so a broken extract shows "Expand-Archive failed" with no clue which file was involved — make sure the thrown error from Process.run still carries stderr (and ideally the resolved OPENCODE_ARCHIVE_PATH value) for debuggability.

3. packages/opencode/test/util/archive.test.ts:7 — the guard if (process.platform !== "win32") return makes the test silently pass on Linux/macOS CI; prefer test.skipIf(process.platform !== "win32") so the skip is visible in reports and someone notices when zero Windows runs happened in a PR touching Windows-only behavior.

4. Nit — coverage gap worth closing while here: the same literal-path hazard usually applies to the non-Windows branch (tar/unzip with odd filenames) and to any sibling helpers in this module interpolating paths into shell strings — a quick audit comment or follow-up ticket reference would lock the scope of the fix.

Overall: correct, minimal security/robustness fix with a test that exercises exactly the reported pathology (apostrophes + brackets in archive and destination names) end-to-end via real PowerShell. Nice. Thanks!

AI code review — automated review for reference; please use your judgment.

• packages/opencode/src/util/archive.ts:9 — strong fix: moving paths out of the interpolated command string into env vars eliminates both the literal-path breakage (', [, ] in names) and a PowerShell injection vector the old quoting had. -LiteralPath is the right parameter.
• packages/opencode/test/util/archive.test.ts:7 — good regression case with apostrophes and brackets in both source and destination names. Since the body early-returns off-Windows, confirm Windows CI actually runs this suite, otherwise it's dead coverage locally.
• Nit: consider asserting that a malicious-looking name like foo'; Remove-Item -Recurse ~; 'bar.zip also extracts safely — that's the property this fix really guarantees.
• No blocking issues found.