refactor: simplify command architecture through local ownership

[francoischalifour]

The CLI’s source structure no longer reflected its public command tree. Command definitions, argument composition, execution helpers, and tests were distributed across broad shared modules and a generic operation/effect framework.

This made small command changes difficult to review: understanding one command often required tracing indirect builders, Citty types, shared registries, ambient runtime state, and tests located elsewhere.

Proposed solution

Restructure the CLI around explicit, local command ownership:

commands/<family>/index.ts
commands/<family>/<command>.ts
commands/<family>/<command>.test.ts
commands/<family>/lib/*

• The directory tree now shows which commands exist.
• Each command declares its public definition at the top of its module.
• Family-specific helpers live under that command family’s lib/.
• Top-level lib/ contains only behavior shared across command families.
• Unit tests are colocated with their subjects; root tests remain black-box CLI tests.

Hide Citty behind the CLI-owned Command, defineCommand, and defineArgs APIs. Runtime, output, and execution dependencies are bound once at the root and passed explicitly instead of being accessed through compatibility facades or ambient state.

Replace the generic operation/effect framework with a direct command flow:

1. parse arguments;
2. construct a plain request value;
3. execute it;
4. present the response.

Declarative request values remain the seam for a future dry-run mode, without maintaining a generic execution framework before dry-run exists.

Shared arguments are composed from their semantic owners—resources, files, timeouts, formats, and presentation options—so commands expose only flags they actually support.

Higher-level tests and correctness

Tests now exercise commands through the public runtime and user-visible flows instead of calling exported implementation helpers. This made important behavioral gaps observable and allowed the corresponding fixes to be covered at the same level:

• browser login persists the control-plane endpoint used to authenticate;
• logging into another organization preserves the existing authenticated profile;
• fresh-profile, lakehouse-only, and --replace-profile login flows behave correctly;
• clearing a login removes all stored OAuth token state;
• unexpected macOS Keychain deletion failures stop profile deletion instead of silently leaving credentials behind;
• catalog request failures are preserved rather than masked by parallel work.

Duplicate suites and test-only production exports were removed while retaining these higher-value behavioral scenarios.

Result

The branch makes command ownership visible, reduces indirection and production exports, removes circular dependencies, and deletes more code than it adds while preserving the public CLI surface.