PD-5781 Fix peer review i18n in print view

[cryptalith]

PD-5781

Problem

The peer review heading is the only print-view string with placeholders, and it was broken in every locale — not falling back to English, but rendering truncated with both counts gone:

	rendered
before	Revisión por pares ($
after	Revisión por pares (7 revisiones de 3 publicaciones/concesiones)

@angular/localize emitted no diagnostic, so this shipped silently.

Root cause

fetch-orcid.js is a plain asset, so ng extract-i18n never sees it. normalize-xlf.prebuild.ts parses the $localize calls out of the file instead, and its placeholder converter only matched UPPERCASE names:

rawSource.replace(/\$\{[^}]*\}:([A-Z0-9_]+):/g, '{$$$1}')

The source uses camelCase (:reviewCount:), so nothing matched and the raw ${reviewsCount}:reviewCount: text went verbatim into the XLF.

Fixing the name pattern alone would not have worked. Xliff1TranslationParser only recognises real <x id="..."/> elements, so the {$NAME} text form that converter aimed for parses as literal content, leaves the message with zero placeholders, and truncates the translation at the first $.

Changes

• Emit real XLIFF <x id="..."/> placeholder elements. These are carried through the xml2js Builder as sentinels, since it escapes any markup found in a text node; the sentinels never reach disk.
• Always regenerate printView.* units from fetch-orcid.js instead of only adding them when absent, so re-parsing a unit that already holds <x/> cannot degrade it. Verified idempotent across repeated runs.
• Convert the locale targets in place, preserving the placeholder reordering translators applied in tr and zh-TW.
• Add a build-time check: fails on leftover legacy syntax, warns when a target drops a placeholder (which inlines cleanly but silently drops the value).

<x/> is the standard XLIFF 1.2 form Angular already emits elsewhere, and Transifex already round-trips it here — 7 translated targets per locale contain it today. The previous raw-text form was the outlier.

Verification

• All 16 translated locales render both counts, run through the real makeEs2015TranslatePlugin pass; uk/ca correctly fall back to English.
• Full suite: 721 specs, 0 failures. I confirmed the peer review spec actually executes by temporarily breaking it.
• messages.xlf is a one-line change — the usual regeneration churn was kept out.

Follow-ups (not in this PR)

• Push to Transifex before merging so translations stay on the <x/> form; the new check fails the build if a pull brings the old syntax back.
• Pre-existing: writeXlf's xml2js round-trip does not preserve mixed content, so the ~32 Angular-extracted units in messages.xlf have their <x/> elements moved to the end of each source on every build. Confirmed independent of this change (the unmodified script from main reproduces it). Tracked separately.

[amontenegro]

Task linked: PD-5781 Fix Peer Review i18n in Print View