test(opencode): isolate memory in cli fixtures

[LeXwDeX]

Summary

• seed a valid global MEMORY config in the shared CLI subprocess fixture
• keep asynchronous MEMORY startup from consuming prompt responses owned by CLI tests
• leave first-run MEMORY model selection covered by the dedicated MEMORY suite

Diagnosis

After PR #215, every fresh CLI test home started MEMORY initialization against the same FIFO fake-LLM queue used by the foreground prompt. The hidden initializer consumed the response prepared for opencode run, so the foreground request received the fixture fallback ok.

Verification

• red: run-process.test.ts reproduced the CI result with 5 pass / 8 fail
• green: run-process.test.ts 13 pass / 0 fail
• CLI + MEMORY suite: 377 pass / 5 skip / 0 fail
• repository lint: 4852 warnings / 0 errors (ratchet met)
• pre-commit package typechecks: 29 / 29 passed
• Prettier and git diff --check: passed

The desktop sandbox cannot provide a valid full-package run because nested Bun, PTY, and LSP subprocesses inherit restricted parent-directory/preload access. The post-merge Linux Unit Tests job remains the authoritative full-suite verification.