fix(taskctl): adversarial-pipeline prompt missing critical review instructions

[randomm]

Task Description

Several adversarial review failures observed in live pipeline runs reveal gaps in the adversarial-pipeline agent prompt:

Problems Observed

1. Wrong test directory — adversarial ran bun test from project root instead of packages/opencode, getting "do-not-run-tests-from-root" error
2. Scope expansion not caught — developer added out-of-scope tests; adversarial approved them
3. Cross-platform assumption missed — expect(tmp.path).not.toContain('/tmp/') fails on Linux; first adversarial caught it, second approved the same code anyway
4. Inconsistent verdicts — second adversarial APPROVED despite first adversarial finding ISSUES_FOUND on identical code

Required Prompt Additions

Test execution (fix wrong directory):

Run tests from packages/opencode directory ONLY:
  cd <worktree>/packages/opencode && bun test
  cd <worktree>/packages/opencode && bun run typecheck
Never run from project root or worktree root.

Scope enforcement:

Check: Does the implementation add ANYTHING not in the task description or acceptance criteria?
- New tests not covering the implementation → ISSUES_FOUND (MEDIUM)
- New functions, helpers, or features not requested → ISSUES_FOUND (HIGH)
- Scope expansion is a violation even if the code is correct

Cross-platform check:

Check: Are there platform-specific assumptions?
- Path assertions hardcoding /var/folders (macOS only) or /tmp (Linux)
- OS-specific API usage without fallbacks
- These are CRITICAL if they will fail on common platforms

Explicit APPROVED criteria:

APPROVED only if ALL true:
- All acceptance criteria met
- bun test passes (from packages/opencode)
- bun run typecheck passes (from packages/opencode)  
- Zero CRITICAL or HIGH issues
- No scope expansion beyond task description
- No cross-platform assumptions that will break

ISSUES_FOUND if ANY:
- MEDIUM/LOW quality issues OR out-of-scope additions

CRITICAL_ISSUES_FOUND if ANY:
- CRITICAL/HIGH bugs, test failures, typecheck failures, cross-platform breaks

Quality Gates (Non-Negotiable)

• TDD: existing adversarial prompt tests must still pass
• All linting passes
• Local verification complete

Acceptance Criteria

• Adversarial runs tests from correct directory (packages/opencode)
• Adversarial flags out-of-scope additions as ISSUES_FOUND
• Adversarial checks for cross-platform path assumptions
• APPROVED/ISSUES_FOUND/CRITICAL criteria are unambiguous and consistent