fix(cli): keep bulk JSON output parseable [EXT-70]

[ruby-automation]

Summary

• reject confirmation and partial project/assignee prompts in JSON mode with stderr diagnostics before mutation
• emit one JSON value for ID and bulk move dry-runs and no-match results
• preserve text-mode interaction while routing prompt-required JSON calls away from stdout
• preserve EXT-69's fail-closed destructive confirmations after integrating current main
• document the Phase 12 JSON contract

Linear issue: https://linear.app/the-rubyists/issue/EXT-70/keep-json-stdout-valid-when-bulk-commands-require-prompts

Verification

• mise exec -- mix setup — passed
• mise exec -- mix ci — passed (58 root tests, 618 app tests, Credo clean, audits clean)
• focused mutation, move, and prompt tests — passed (138 tests)
• GitHub Actions run 36374663750 — Test and change detection passed; Burrito regression skipped because no Burrito-impacting files changed

The branch integrates current main with a regular merge, so the update was pushed without force-pushing.

[ruby-automation]

Automated review is approved and there are no review comments to action. The first Test run failed only because the PR title was not Conventional Commits compliant; I corrected it to fix(cli): keep bulk JSON output parseable [EXT-70], and the rerun passed.

[ruby-automation]

Rework completed for the EXT-69 integration review:

• Addressed the requested conflict fix by merging current main (which contains EXT-69) into this branch without force-pushing.
• Updated both text-mode destructive move confirmations to use Prompt.confirm_destructive?/1, preserving EXT-69's fail-closed behavior for blank or EOF input.
• Preserved the JSON prompt guards, exact-match resolution, and both Phase 12 decision entries.
• No other review comments were outstanding; the prior automated review was approved.

Verification:

• mise exec -- mix ci — passed (58 root tests, 618 app tests, Credo clean, audits and usage-rule checks clean).
• Focused mutation/move/prompt suite — passed (138 tests).
• GitHub Actions run 36374663750 — Test and change-detection checks passed; Burrito regression skipped because no Burrito-impacting files changed.