1. Global config fallback: relative artifact paths are now resolved against
the global config directory (not the project root) when loading from fallback.
Absolute paths are left unchanged. Project-level config behavior is unaffected.
2. EMBEDDING_BATCH_SIZE: replaced Number.parseInt with Number() + Number.isInteger()
so that inputs like "64abc", "1.5", and "" are correctly rejected instead of
silently accepted.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>