docs(personality): add MBTI asset taskline retrospective

[fermatmind]

What changed

• add a dated MBTI personality asset taskline retrospective index
• document the cross-repo PR timeline and current nine-URL completion boundary
• document backend/frontend authority, release gates, and effective indexability
• record recurring incidents, root causes, and durable prevention checks
• add a read-only scan/operations runbook and next-phase roadmap
• link the retrospective from the personality SEO operations index

Why

The existing personality operations README still described the July 4 dry-run phase. The task line has since completed its first nine-URL CMS/import/indexability/discoverability/GSC loop, while several operational incidents exposed reusable lessons. A durable cross-PR summary is needed so later scans distinguish verified production facts, GitHub merge facts, and potentially stale ledger state.

Validation

• structured jq reads against the merged INDEX-24R and GSC-25 JSON artifacts
• local referenced-doc path validation across all six retrospective files
• git diff --cached --check
• exact changed-file scope review: seven documentation files only

Deferred items

• no runtime, CMS, API, sitemap, LLMS, indexability, deploy, GSC, or PR-train ledger changes
• GSC 7/14/28 day read-only monitoring remains a follow-up operation
• remaining MBTI profiles and comparisons still require separate evidence-gated batches

Repository rule impact

Documentation only. Content authority and publishing ownership remain unchanged: fap-api/CMS is authoritative and fap-web only consumes and validates public authority surfaces.