Support importing Feishu/Lark credentials from lark-cli

[jolestar]

Context

AgentInbox wants Feishu/Lark credentials to be owned by UXC, with AgentInbox storing only a uxcAuth / configRef reference.

On a machine with lark-cli installed and logged in, the CLI already has enough local configuration to identify the active Feishu/Lark app and user session:

• lark-cli profile list shows the active app/profile and brand
• lark-cli auth status shows token status and user identity
• ~/.lark-cli/config.json stores appId and an appSecret reference such as { "source": "keychain", "id": "appsecret:<appId>" }
• the secret itself is stored through lark-cli's secure storage/keychain layer, not as plaintext config

Today UXC has auth credential import --from gh, but no equivalent import path for lark-cli. Operators must either configure a Feishu credential manually in UXC or copy secret material by hand, which is exactly the boundary we want to avoid.

Proposal

Add a UXC credential import source for lark-cli:

uxc auth credential import feishu-tenant --from lark-cli

Optional flags could include:

uxc auth credential import feishu-tenant --from lark-cli --profile <profile>
uxc auth credential import feishu-tenant --from lark-cli --skip-binding
uxc auth credential import feishu-tenant --from lark-cli --binding-id <id>
uxc auth credential import feishu-tenant --from lark-cli --force

The import should create a bearer credential with Feishu/Lark tenant-token bootstrap configured from the imported app credentials, and should add an endpoint binding for the provider OpenAPI endpoint unless --skip-binding is passed.

Desired Credential Shape

For Feishu:

• credential id: user-supplied
• auth type: bearer
• fields:
  • app_id
  • app_secret
• bootstrap:
  • token endpoint: https://open.feishu.cn/open-apis/auth/v3/tenant_access_token/internal
  • request JSON: { "app_id": "{{field:app_id}}", "app_secret": "{{field:app_secret}}" }
  • access token pointer: /tenant_access_token
  • expires-in pointer: /expire
  • success code pointer: /code
  • success code value: 0
• binding:
  • host: open.feishu.cn
  • path prefix: /open-apis
  • scheme: https

For Lark global, the host/token endpoint should match the active lark-cli app brand/endpoint conventions.

Safety Requirements

• Do not print app secret or access tokens in command output.
• Preserve UXC's normal masked auth credential info output behavior.
• If lark-cli stores the app secret in keychain/encrypted storage, import should read through the same supported local mechanism instead of requiring manual plaintext copying.
• If the secret cannot be read because keychain access is blocked, fail with a clear remediation message.
• Do not switch or remove the active lark-cli profile.

Acceptance Criteria

• uxc auth credential import <id> --from lark-cli imports the active lark-cli app credential into UXC.
• uxc auth bootstrap refresh <id> succeeds after import.
• uxc auth binding match https://open.feishu.cn/open-apis/im/v1/messages matches the imported credential when binding creation is enabled.
• Import output masks all secret/token material.
• --profile <profile> imports a non-active lark-cli profile without changing lark-cli's active profile.
• --skip-binding creates only the credential/bootstrap config.

Why This Matters

This keeps the product boundary clean:

• lark-cli remains a convenient local auth/bootstrap tool for users
• UXC becomes the reusable credential owner for provider API execution
• AgentInbox can reference Feishu/Lark auth by UXC credential id without storing app secrets

[simonlpaige]

Looking at the existing auth credential import --from gh implementation in crates/uxc-auth/src/credential/importers/github.rs and the lark-cli configuration structure, here are a few technical considerations:

1. Secret material handling - The GitHub importer reads tokens directly from config files. For lark-cli, the appSecret lives in the system keychain (macOS Keychain, Secret Service, or Windows Credential Manager depending on platform). You'll need to add a keychain reader abstraction - security find-internet-password on macOS, secret-tool on Linux, or credential-manager on Windows. The keyring crate could standardize this.

2. Token bootstrapping - Unlike GitHub's static PAT, a Feishu tenant token requires an OAuth-style exchange: appId + appSecret → tenant_access_token (TTL ~2h). The imported credential should either (a) store the raw appId/appSecret and perform the exchange on each UXC invocation, or (b) fetch the token once and store it with a refresh mechanism. Option (a) is simpler but means UXC needs the keychain dependency at runtime, not just import time.

3. Profile detection - lark-cli profile list outputs JSON. The active profile's appId maps to the keychain entry via "id": "appsecret:<appId>". Consider resolving --profile early and validating the keychain entry exists before attempting import.

4. Edge case - If lark-cli uses a custom LARK_CLI_CONFIG_DIR env var, the default ~/.lark-cli/config.json path won't work. The import should respect that.