Which ignore source should a Biome monorepo use for generated and vendored files?

A monorepo needs to decide whether Biome should discover files using the repository's VCS ignore rules or explicit Biome ignore patterns for generated and vendored paths. The choice affects whether exclusions are shared across tools or maintained separately for Biome alone.

VCS integration offers repository-wide policy, but explicit Biome patterns keep tool-specific decisions isolated. Because Biome version releases can change option names, defaults, and ignore-matching behavior, configuration from an older release may not apply unchanged. In a monorepo, the ignore source and repository root must also remain consistent across local, editor, and CI execution to avoid divergent file-discovery results.

A path excluded from Biome processing receives neither lint diagnostics nor formatting, so complete exclusion should be intentional for each file class. Does relying on VCS ignore files create hidden coupling with other tools, or do explicit Biome patterns introduce unnecessary maintenance drift? Which approach better preserves consistent file discovery across environments while keeping generated and vendored files out of lint and format checks?