Feature request: support multiple vault paths via ATLAS_VAULT_ROOTS

[handweavingacademy]

Feature Request: Multiple Vault Path Support (ATLAS_VAULT_ROOTS)

Use Case

ATLAS_VAULT_ROOT currently accepts a single path, but VaultExtractor already accepts vault_roots: list[Path] and iterates over all of them. The multi-vault capability exists at the library layer but isn't exposed through configuration.

Concrete scenario: Two users (e.g. a business owner and an operations manager) each run their own Atlas instance. Each person has:

• A shared business Obsidian vault (synced via Obsidian Sync — same content, separate local copies)
• • A personal Obsidian vault
    Each user wants their Atlas to ingest both vaults simultaneously so beliefs from personal notes and business notes connect in a single graph. Separate instances preserve private beliefs while the shared vault provides common business context.

Proposed Change

A minimal change to atlas_core/daemon/cycle.py (and the same in scripts/first_real_run.py):

# Replace:
vault_root = Path(os.environ.get("ATLAS_VAULT_ROOT", ...))
if vault_root.exists():
    orch.register(VaultExtractor(quarantine=quarantine, vault_roots=[vault_root]))

# With:
vault_roots_env = os.environ.get("ATLAS_VAULT_ROOTS", os.environ.get("ATLAS_VAULT_ROOT", ""))
vault_roots = [Path(p.strip()) for p in vault_roots_env.split(":") if p.strip()] if vault_roots_env else []
vault_roots = [r for r in vault_roots if r.exists()]
if vault_roots:
    orch.register(VaultExtractor(quarantine=quarantine, vault_roots=vault_roots))

Adds ATLAS_VAULT_ROOTS (colon-separated, same convention as PATH) while remaining fully backward-compatible with the existing single-path ATLAS_VAULT_ROOT.

Why This Is Low-Effort

VaultExtractor already does all the work — this is purely a config exposure change. No changes to the core engine, belief graph, or ingestion logic required. Happy to submit a PR if this direction looks good.