feat(skills): offer to install skills on first run

[JackNDwyer]

What

• On a run in a terminal, if a coding agent is on the machine and no LiveKit skills are installed (globally or in the current project), lk asks once whether to install them globally. Yes runs the same install as lk skills install --global.
• It runs before any command, ahead of sign-in, so API-key, lk project add and self-hosted users see it too.
• It never blocks a non-interactive run. Without a terminal, or with --yes (for example, a coding agent calling lk), it prints a one-line tip instead. CI, --quiet, --json and LK_NO_SKILLS_PROMPT=1 skip it entirely.
• The answer is saved in the CLI config (skills_prompted), so it's asked only once. Declining also stops the tip.
• It skips the skills commands, help, version and completion, and lk agent init, which has its own skills offer.
• An install failure is reported as a warning, and the command the user ran still runs.

Why

Coding agents building LiveKit agents often don't have LiveKit's skills (DEVX-840), especially when starting from an empty folder, where no repo file can point them there. This installs the skills when the CLI is first used, however it was installed (Homebrew can't run this step itself). Ticket: DEVX-843. The cross-platform curl installer from the same ticket is in #1057.

Pairs with the template-side change in livekit-examples/agent-starter-python#114 and livekit-examples/agent-starter-node#75.

How to verify

1. Build this branch and, in a terminal, run any command with a fresh home folder that has a coding agent's config folder: HOME=$(mktemp -d) sh -c 'mkdir $HOME/.claude && lk token create --list --api-key k --api-secret s'. Expect the prompt. Yes installs seven skills into ~/.claude/skills and adds the Docs MCP server, then the command runs. No prints a skip line, then the command runs.
2. Run it again with the same HOME: no prompt.
3. Run with </dev/null (no terminal) on a fresh HOME: one Tip: line on stderr, no prompt. Add --quiet, CI=1 or LK_NO_SKILLS_PROMPT=1: no tip.

Unit tests cover the decision table, the installed-skills check, and resolving the leaf command from the root Before hook. I tested both prompt answers and the non-interactive paths with a local build; the prompt was driven through script rather than a real terminal.

🤖 Generated with Claude Code

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