Migrate internal/auth and internal/output to consume shared basecamp/cli module

[jeremy]

What

Consume github.com/basecamp/cli v0.1.0 (merged in basecamp/cli#1) from basecamp-cli, validating the extraction and eliminating ~580 lines of duplicated code.

Changes

1. Add shared module dependency — pins github.com/basecamp/cli@v0.1.0
2. Migrate internal/output — re-exports exit codes, error codes, ExitCodeFor, NormalizeData, TruncationNotice, TruncationNoticeWithTotal via immutable wrapper functions. Type-aliases Error for zero-cost errors.As compatibility. Keeps ErrAuth and ErrForbiddenScope local (app-specific hint strings).
3. Migrate internal/auth — replaces keyring implementation (~230→70 lines) with a typed wrapper around credstore.Store. Replaces PKCE helpers with pkce.GenerateVerifier/Challenge/State. Replaces waitForCallback with inline listener + oauthcallback.WaitForCallback (with 5-minute timeout preserved).

What stays local

• surface — fundamentally different approach (Go library walks cobra tree in-process vs. shell scripts invoke binary)
• profile — tightly integrated into basecamp-cli's config system
• ErrAuth/ErrForbiddenScope — app-specific hint strings
• Credentials struct, Response/ErrorResponse envelopes, presenter, TUI, renderer — app-specific

Verification

• make check passes (fmt, vet, lint, test, e2e, naming, surface, provenance, tidy)
• All 257 e2e tests pass
• go-keyring remains a direct dependency (still imported by doctor.go and migrate.go for keyring availability checks)
• go mod tidy is idempotent

[Copilot]

Pull request overview

Migrates internal/output and internal/auth to consume the newly extracted shared module github.com/basecamp/cli, reducing duplicated code and keeping Basecamp CLI’s app-specific behavior where needed.

Changes:

• Add github.com/basecamp/cli dependency and re-export shared output error/codes/normalization helpers.
• Replace the local keyring/file credential store with a typed wrapper around credstore.Store.
• Replace in-repo PKCE and callback-wait logic with shared pkce and oauthcallback utilities.

Reviewed changes

Copilot reviewed 8 out of 9 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
internal/output/errors.go	Type-aliases shared output.Error and re-exports shared error constructors + AsError, keeping app-specific auth/scope hints local.
internal/output/codes.go	Re-exports shared exit codes, error codes, and ExitCodeFor.
internal/output/envelope.go	Re-exports shared NormalizeData and truncation notice helpers; removes local implementations.
internal/output/envelope_benchmark_test.go	Removes benchmarks tied to deleted local normalization helpers.
internal/auth/keyring.go	Replaces local keyring + file fallback implementation with a typed wrapper over credstore.Store.
internal/auth/auth.go	Switches PKCE/state generation and OAuth callback waiting to shared pkce/oauthcallback.
internal/auth/auth_test.go	Updates tests to use the new store wrapper; removes tests for deleted local PKCE/key helpers and file-permission/atomic-write details.
go.mod	Adds github.com/basecamp/cli dependency.
go.sum	Adds checksums for github.com/basecamp/cli.

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[Copilot]

Pull request overview

Copilot reviewed 8 out of 9 changed files in this pull request and generated 3 comments.

Comments suppressed due to low confidence (1)

internal/auth/auth_test.go:35

• TestNewStore() calls NewStore() without disabling the keyring, so the test’s behavior can vary by environment and may touch the user/system keychain (or require desktop services like DBus). Consider setting BASECAMP_NO_KEYRING in this test (or using newTestStore) so unit tests are deterministic and avoid side effects.

func TestNewStore(t *testing.T) {
	tmpDir := t.TempDir()
	store := NewStore(tmpDir)

	// Store should be created (may or may not use keyring depending on system)
	require.NotNil(t, store, "NewStore returned nil")
}

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