latest symlink is environment-blind in multi-environment workflows

[stack72]

Problem

When the same model runs across multiple environments, all data versions are stored under a single path with one latest symlink:

.swamp/data/command/shell/{model-id}/result/
├── 1/       (dev run)
├── 2/       (prod run)
├── 3/       (dev run)
└── latest -> 3   # always points to most recent, regardless of environment

The latest symlink points to whichever version was written most recently — in this case, version 3 from a dev run. There is no concept of "latest for prod" or "latest for staging" at the filesystem level.

Why This Matters

The latest symlink serves two purposes:

1. Quick access — users browsing the data directory can find the most recent output
2. CEL resolution — expressions like model.deploy-app.resource.result.latest.attributes.* resolve through this symlink

In a single-environment setup, latest always points to the most recent run, which is correct. But in a multi-environment setup, latest is misleading:

• A user looking at latest after a dev run might think it's the current prod state
• A CEL expression referencing latest in a prod workflow might resolve to dev data if dev ran more recently
• There is no way to browse to "latest prod result" without searching through version metadata

This creates a correctness hazard: the most convenient and obvious access path (latest) returns environment-incorrect data in multi-environment scenarios.

Current Workaround

Users can use swamp data search --tag environment=prod to find the right version, but this requires knowing to avoid the latest symlink and using tag-based queries instead. CEL expressions have no equivalent workaround — data.latest() and the implicit latest path always resolve to the globally most recent version.

Use Case

A deployment workflow runs multiple times per day across dev, staging, and prod. A downstream monitoring model references the deployment model's output via CEL to check the last deployed version. Without environment-aware latest resolution, the monitoring model reports whichever environment deployed most recently, not the specific environment being monitored.

This issue is related to the need for tag-filtered data access in CEL (see related issue), which would solve the CEL side. This issue specifically tracks the filesystem-level latest symlink behavior for users browsing data directly.

[github-actions]

Hi @stack72, thanks for opening this issue!

We appreciate you taking the time to report it. A maintainer will review it as soon as possible.

In the meantime, please make sure you've included all relevant details (steps to reproduce, expected vs actual behaviour, swamp version, etc.) to help us triage it quickly.

[stack72]

Closing in favor of a unified approach: adding a name field to dataOutputOverrides with CEL expression support (see #384). By varying the data name per environment (e.g., prod-result, dev-result), each data name gets its own latest symlink — prod-result/latest always points to the latest prod version, regardless of how many dev runs happened after it.