chore(cli): migrate @fern-api/lazy-fern-workspace to use CliError

[FedeZara]

Description

Migrates @fern-api/lazy-fern-workspace to use explicit CliError error codes on every failAndThrow / failWithoutThrowing call site.

This is one of the package migration PRs that follow the error classification system introduced in #14749.

Changes Made

Assigned typed error codes across call sites in packages/cli/workspace/lazy-fern-workspace/src/. Also added missing CliError imports to all files that reference CliError.Code.

Error codes used

Code	Usage
CONFIG_ERROR	Missing workspace configuration, invalid workspace structure
PARSE_ERROR	Failed OpenAPI/AsyncAPI parsing, overlay application failures
RESOLUTION_ERROR	Protobuf resolution failures, dependency loading errors
NETWORK_ERROR	Failed dependency downloads

Files touched (grouped by area)

• Workspace loading: LazyFernWorkspace.ts, utils/loadDependency.ts
• Loaders: loaders/applyOverlays.ts, loaders/mergeWithOverrides.ts
• Protobuf: protobuf/ProtobufIRGenerator.ts, protobuf/ProtobufOpenAPIGenerator.ts

Testing

• Existing tests pass (pnpm test, excluding e2e and pre-existing environment failures)

[FedeZara]

• chore(cli): migrate @fern-api/lazy-fern-workspace to use CliError #15005 👈 (View in Graphite)
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.