v0.40.0

Added

• OC-CFG-014: Invalid subagent_depth Value (#1214). OpenCode v1.18.2 added a top-level subagent_depth field (Schema.optional(NonNegativeInt)); the new rule warns when the value is present but not a non-negative integer (string, float, bool, negative number). "subagent_depth" is also added to KNOWN_TOP_LEVEL_KEYS so valid v1.18.2 configs no longer trigger the OC-004/OC-CFG-003 unknown-key false positive. Source: https://github.com/anomalyco/opencode/releases/tag/v1.18.2. Rule count 436 → 437. Closes #1214.