Implement plan 11: JSearch removal and tailoring documentation

Read entire approved plan first from local planning checkout only when its HEAD equals a2557b2ad40e06e1e63eb655f286e6a78fe6bf0d; otherwise use pinned git show fallback below. Then read current worktree AGENTS.md, referenced issue/domain instructions, relevant ADRs, /Users/amruth/.codex/RTK.md, and /Users/amruth/.agents/skills/documentation-writer/SKILL.md. Plan supplies document type, audience, goal, scope, and approved structure; do not pause for routine outline approval. Portable fallback: fetch PR #3455 and use git show a2557b2ad40e06e1e63eb655f286e6a78fe6bf0d:plans/11-job-search-policy.md.

Do not spawn subagents. Do not touch coordinator ledger or another worktree. Do not merge, mutate issues, push, or create PR.

Required execution:

Confirm clean worktree, fetch current origin/main, rename branch codex/issue-3010-jsearch-docs, run exact drift command, fetch live #3010 body/comments/state/linked PRs, and run root intent discovery before edits.
Verify release history, current job-search redirect, agent tools, provider/model capability policy, and attachment UI before wording claims. Stop if release history contradicts removal attribution or documented UI steps do not exist.
Modify only docs/changelog/index.mdx, docs/guides/using-ai-agent.mdx, and docs/guides/ai-agent-tools.mdx.
Add factual v5.1.0 migration note, current controlled tailoring workflow using plan's exact synthetic job description, review and undo guidance, pasted/attached-content behavior, and live-search capability distinction. No unverified removal motive, paid JSearch restoration, stale model list, provider credentials, or promise that chat is equivalent structured search.
Run exact API tool/capability tests and plan's focused rg, markdown lint, git diff --check, and three-file name-only gate. Record real-provider/browser workflow as optional unavailable validation when not run.
Self-review every acceptance criterion. Commit with normal message. Leave branch local for independent review.

Write report .orchestration/plan-11-implementation.md: verified facts vs uncertainty, live state, drift, exact commit/files, commands/results, skipped gates, risks, issue coverage, PR status (not created). Final response: status, commit, one-line tests, report path, concerns; at most ten lines.