feat(cli): deprecate dev mode in favor of lk agent dev

[rosetta-livekit-bot]

Summary

Ports the applicable behavior from livekit/agents#6656.

• Add migration guidance to direct dev --help output.
• Warn when direct legacy dev mode starts, while suppressing the warning when --cli-addr shows the process was launched by lk agent dev.
• Leave the TCP console --connect-addr path unchanged because it is the path driven by lk agent console, not the legacy local console deprecated by the source PR.
• Add a patch changeset for @livekit/agents only.

Source diff coverage

Authoritative source PR #6656 coverage

Source file	Classification	Target coverage
livekit-agents/livekit/agents/cli/_legacy.py	Adapted	The legacy dev help and startup warning are adapted in agents/src/cli.ts using Commander and the existing Pino logger. The warning is suppressed for lk agent dev launches identified by --cli-addr. The source file's legacy Rich local-console changes are not applicable because agents-js has no equivalent legacy console; its console --connect-addr command is the TCP path PR #6656 explicitly leaves untouched.

The authoritative source diff adds or modifies no tests, so there are no source tests to port. No source files or applicable behavior were silently omitted.

Test plan

• pnpm test agents (111 files passed; 1544 tests passed, 5 skipped)
• pnpm build:agents
• pnpm --filter @livekit/agents lint (passes with existing warnings)
• pnpm exec prettier --check "agents/src/cli.ts" ".changeset/deprecate-legacy-dev-mode.md"
• Built CLI smoke check: dev --help displays the deprecation and migration URL

Source: livekit/agents#6656

---

Ported from livekit/agents#6656

Original PR description

Console and dev modes are being removed from the Python framework. This adds the deprecation notices first, pointing users at lk agent console / lk agent dev and the CLI setup docs.

Surfaces, all in the legacy rich CLI:

• Console startup notice, using the existing tagged-print pattern (same mechanism as the Recording notice), so it shows in both audio and text mode:

    Agents   Starting console mode 🚀
 Deprecated  console mode is deprecated and will be removed in a future release.
             Use lk agent console instead: https://docs.livekit.io/reference/developer-tools/livekit-cli/#setup

• dev logs a deprecation warning at startup (alongside the existing auto-reload warning).
• console --help and dev --help both read Deprecated: use lk agent <cmd> instead.

run_app already emits a generic DeprecationWarning for the whole legacy Python CLI, so no second command-specific warnings.warn here — this fills the gap in per-command migration guidance.

The TCP console in cli.py is untouched; that is the path lk agent console drives, not the one being deprecated.

[changeset-bot]

🦋 Changeset detected

Latest commit: 59966ce

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 39 packages

Name	Type
@livekit/agents	Patch
@livekit/agents-plugin-anam	Patch
@livekit/agents-plugin-anthropic	Patch
@livekit/agents-plugin-assemblyai	Patch
@livekit/agents-plugin-azure	Patch
@livekit/agents-plugin-baseten	Patch
@livekit/agents-plugin-bey	Patch
@livekit/agents-plugin-cartesia	Patch
@livekit/agents-plugin-cerebras	Patch
@livekit/agents-plugin-deepgram	Patch
@livekit/agents-plugin-did	Patch
@livekit/agents-plugin-elevenlabs	Patch
@livekit/agents-plugin-fishaudio	Patch
@livekit/agents-plugin-google	Patch
@livekit/agents-plugin-hedra	Patch
@livekit/agents-plugin-hume	Patch
@livekit/agents-plugin-inworld	Patch
@livekit/agents-plugin-krisp	Patch
@livekit/agents-plugin-lemonslice	Patch
@livekit/agents-plugin-liveavatar	Patch
@livekit/agents-plugin-livekit	Patch
@livekit/agents-plugin-minimax	Patch
@livekit/agents-plugin-mistral	Patch
@livekit/agents-plugin-mistralai	Patch
@livekit/agents-plugin-neuphonic	Patch
@livekit/agents-plugin-openai	Patch
@livekit/agents-plugin-perplexity	Patch
@livekit/agents-plugin-phonic	Patch
@livekit/agents-plugin-protoface	Patch
@livekit/agents-plugin-resemble	Patch
@livekit/agents-plugin-rime	Patch
@livekit/agents-plugin-runway	Patch
@livekit/agents-plugin-sarvam	Patch
@livekit/agents-plugin-silero	Patch
@livekit/agents-plugin-soniox	Patch
@livekit/agents-plugin-tavus	Patch
@livekit/agents-plugins-test	Patch
@livekit/agents-plugin-trugen	Patch
@livekit/agents-plugin-xai	Patch

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Click here if you're a maintainer who wants to add another changeset to this PR

[devin-ai-integration]

✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no potential bugs to report.

View in Devin Review to see 1 additional finding.