Unify CLI cluster resolution so all commands respect per-app state (MIR-832)

[phinze]

When a user runs cluster switch in an app directory, it saves the chosen cluster to both the global config and per-app state. Commands using AppCentric (like cluster current, deploy) would read that per-app state and target the right cluster. But commands using ConfigCentric (like route list, sandbox list, app list) skipped per-app state entirely and fell back to the global active_cluster. So you could see cluster current report "miren01" while route list silently hits a completely different cluster.

The fix teaches ConfigCentric.LoadCluster() itself to check per-app state when running in an app directory, slotted in between the explicit overrides (-C flag, MIREN_CLUSTER env) and the global fallback. This is the minimal change that fixes the inconsistency without restructuring the command hierarchy. With the logic centralized, AppCentric.LoadCluster() drops its parallel implementation and just delegates, and cluster current replaces its bespoke resolution with a LoadCluster() call.

A sweep of the rest of the CLI commands turned up several more that were doing their own ad-hoc resolution instead of going through LoadCluster() — app list, cluster list, cluster export-address, doctor, and doctor auth all got converted. The only intentional exception is deploy's interactive "add a cluster" recovery path, which correctly reads the just-added cluster directly.

Note: doctor could use a deeper rework beyond this scope — it's doing a lot of manual wiring that doesn't quite fit the LoadCluster() model cleanly. Filing a follow-up for that.

Closes MIR-832

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📥 Commits

Reviewing files that changed from the base of the PR and between b9072fa and fa8f081.

📒 Files selected for processing (9)

• cli/commands/app.go
• cli/commands/app_list.go
• cli/commands/cluster.go
• cli/commands/cluster_current.go
• cli/commands/cluster_export.go
• cli/commands/config.go
• cli/commands/config_test.go
• cli/commands/doctor.go
• cli/commands/doctor_auth.go

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📝 Walkthrough

Walkthrough

This PR refactors cluster resolution logic across multiple CLI commands to use a centralized LoadCluster method instead of individual config/state lookups. The config.go file now handles per-app state checking during cluster resolution, falling back to global settings when an active app's state doesn't specify a cluster. Commands including cluster, cluster_current, cluster_export, doctor, and doctor_auth are updated to call opts.LoadCluster() for cluster retrieval. The app.go command delegates to ConfigCentric.LoadCluster, while app_list.go switches from configuration loading to direct cluster loading. Tests are added to validate environment-based and app-scoped cluster resolution paths, including fallback behavior and CLI flag/environment variable overrides.

📝 Coding Plan

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