feat(create): machine-readable --json output and hidden --origin flag

[l2ysho]

Closes #1238. Stacked on #1278 (base = the 1236 wizard branch); rebase onto master after that merges.

Makes apify create machine-readable for agents and the Console "Clone locally" handoff.

What changed

• --json on apify create prints a contract on stdout:

  { "dir", "actorJsonPath", "template", "source": "apify", "nextSteps": [] }

  All progress/info/warning output stays on stderr. On error: non-zero exit, message on stderr, no stdout.
• Hidden --origin console|cli flag (default cli) → recorded in create telemetry for the funnel.
• Small: buildNextSteps() extracted (shared by --json and the success message); templates ls shows JavaScript instead of raw javascript.

Not in scope (deferred, per the epic)

• --source/--git-repo and the git-connect flow → separate sub-issue. So the contract omits remote/gitConnectUrl and hardcodes source: "apify" (the only behavior today).
• --json without --template in a non-TTY still prompts (then fails); agents/Console always pass --template. Routing dependency-install output off stdout in JSON mode is a known robustness gap — left as follow-up (touches shared execWithLog).

Tests

12 create tests (incl. --json contract shape + hidden --origin acceptance) + 27 lib tests. build / lint / format clean; docs regenerated.

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