fix(platform-scripture): Select-All excludes not-in-reference books

[lyonsil]

Summary

Manage Books → Create → Based on template: "Select all" was selecting books that are not present in the reference project — the books the grid renders as disabled. This inflated the selection count and tripped the missing-model preflight prompt for books the orchestrator would only filter out at submit time anyway.

The set that Select-All, the header tri-state checkbox, the selection count, and the "{n} of {m} selected" announcement all derive from (selectableVisibleBooks) now excludes not-in-reference books. It shares a single predicate (isBookNotInCreateReference) with the grid's pill-disabling logic so the grid's "disabled" and the selection logic's "selectable" can no longer drift — the drift that caused this bug.

Root cause

selectableVisibleBooks included disabled (not-in-reference) books, and toggleAllVisible (Select-All) added all of them. The grid disabled those pills and an existing prune effect removed them on reference change, but Select-All re-added them. extensions/src/platform-scripture/src/manage-books-dialog/manage-books-dialog.component.tsx.

Fix

• Extracted two pure helpers into manage-books-dialog.utils.ts (matching the existing deleteConfirmVariant / computeCompareState pure-helper pattern):
  • isBookNotInCreateReference(book, …) — single source of truth for "not creatable from the reference project".
  • computeSelectableVisibleBooks(…) — the genuinely-selectable set, excluding not-in-reference books.
• Rewired selectableVisibleBooks and the grid's disabled condition to both use the shared predicate. The grid change is behavior-preserving (verified equivalent below).

Minimal diff: 3 files, changes confined to one dialog. No opportunistic refactors.

Reproduction & regression evidence (RED → GREEN)

Backend/logic defect — reproduced with a failing unit test, then fixed.

Before (RED):

× computeSelectableVisibleBooks > regression: Create-from-template excludes books not in the reference project (so Select-All cannot select disabled books)
  → expected [ 'GEN', 'EXO', 'LEV', 'NUM' ] to deeply equal [ 'GEN', 'EXO' ]
 Test Files  1 failed (1)
      Tests  1 failed | 32 passed (33)

After (GREEN):

✓ computeSelectableVisibleBooks > regression: Create-from-template excludes books not in the reference project (so Select-All cannot select disabled books)
 Test Files  1 passed (1)
      Tests  35 passed (35)

An independent reviewer ran the Revert Test: removing the fix's .filter(…) fails exactly the regression test and nothing else.

Self-review

Three adversarial reviews (architecture/correctness, scope/clarity, tests):

• Correctness: the grid's disabled condition is provably equivalent to the original (verified by truth table including undefined reference state and empty present-set); no selectableVisibleBooks consumer regresses; the header tri-state now correctly reaches "all selected"; complements (does not conflict with) the existing prune effect; no null/undefined hazards.
• Scope/clarity: tight scope, no dead code, helper extraction justified and pattern-conforming.
• Tests: regression test meaningful, falsifiable (Revert Test confirmed), behavior-focused; added 2 extra coverage cases per review feedback.

A pre-existing, out-of-scope finding (the per-group toggleAllInGroup header does not filter disabled books — cosmetic, and after this fix it no longer affects the count or preflight) was recorded for follow-up rather than expanded into this PR.

Impact & confidence

• User-visible: yes. Severity: medium (spurious preflight prompt + wrong selection count in Create-from-template). Frequency: occasional (Create-from-template when the reference project lacks some destination books). Confidence: ~0.95.

Provenance

Found by the automated quality-sweep run qs-2026-06-26 (cold-scan fallback; the Jira seed was unavailable this run, so the run degraded to backlog + cold scan). Scan dedup key: scan:platform-scripture:selectall-selects-disabled-books.

AI-assisted — generated by Claude Opus 4.8 via the quality-sweep harness.

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