feat: Add schema 2.0 storage, stable workspace IDs, and machine APIs

[maximkrouk]

Summary

Release fxcodex 0.2.0 with stable workspace identities, schema 2.0 storage, expanded machine-readable APIs, and improved Raycast integration.

Highlights

• Assign stable UUIDs to workspaces so references survive renames.
• Migrate schema 1.0 storage to schema 2.0 while preserving existing workspace data.
• Move managed workspace directories from name-based paths to stable ID-based paths.
• Add resumable migration state, storage locking, and migration validation.
• Add versioned JSON responses with lower snake case API keys.
• Add machine APIs for workspace operations, integration attributes, and supported Raycast installation commands.
• Add --workspace-id support for opening workspaces.
• Make commands interactive when required arguments are omitted where appropriate.
• Improve command help and keep the current workspace first in interactive selection.
• Add integration-owned JSON attribute storage.
• Improve universal builds and compatibility with Xcode 27.
• Expand test coverage across migrations, storage, CLI behavior, JSON output, updates, and integrations.

Raycast integration

• Update the extension for the 0.2.0 workspace and status APIs.
• Keep preferences, status, and diagnostics available when the CLI fails.
• Read diagnostics directly where possible and make them copyable.
• Cache workspace results to avoid empty loading flashes.
• Disable destructive actions while a workspace is running instead of hiding them.
• Add workspace name, ID, path, and PID copy actions.
• Improve action labels and status presentation.

The bundled Raycast binary will be replaced with the 0.2.0 release artifact after the CLI release is published.

Documentation

• Update the README, data layout, migration guidance, command examples, and table of contents.
• Document stable workspace identities and the extension-facing API.
• Document commands intentionally excluded from the 0.2.0 machine API.

Machine API exceptions

The following remain intentionally terminal-only in 0.2.0:

• cli and exec, because they launch the potentially interactive Codex CLI.
• Root uninstall, because it removes the executing binary.
• Raycast sync and uninstall.

Breaking changes

• Schema 2.0 storage is not readable by fxcodex 0.1.x.
• Managed workspace directories now use stable workspace IDs instead of workspace names.
• Frontends should use the documented 0.2.0 JSON API and stable workspace IDs.

Validation

• All 123 CLI and client tests pass.
• Universal arm64 and x86_64 builds pass.
• The project builds with the Xcode 27 Swift toolchain.
• Raycast extension build and lint checks pass.