fix(i18n): address the ru review — units, Cyrillic regexes, locale registry

Dose bank
- DRUG_UNIT learns мг / мкг / мл / ЕД / МЕ, so "2,4 мг" anchors a dose again.
- The bank matches verb-first Russian word order too ("принимайте 2 таблетки",
  "пропустите дозу метформина", "начните с 5 мг"), and the Cyrillic drug names
  people actually see on the box; the deferral words ("спросите врача",
  "как назначено") stand those shapes down.

Cyrillic-safe regexes
- \w and \b are ASCII in JavaScript: every stem in the ru bank and in
  population-norms/ru.ts is [а-яё]*, and the word edges are lookarounds
  (?<![а-яёa-z]), so «высокий риск» and «нормальный диапазон» match again.
- coach-prose-grounding: Russian month names in the genitive, a space as the
  thousands separator in parseLocaleNumber and numFrag, and Cyrillic-safe
  edges around the written-date pattern.

Registered everywhere a locale has to be
- targetLanguageName() returns "Russian", so the coach, the period narrative
  and the document descriptions stop saying "write in English".
- i18n-key-tool.mjs, split-description.mjs, LOINC name normalisation (it
  stripped Cyrillic, so no Russian lab name resolved), HOST_TLDS (ru/by/kz/ua),
  no-key-fallbacks (32 tables), country-label, the AUDIT-C standard drink.
- docs/api/openapi.yaml regenerated.

Questionnaires
- The PHQ-9 / GAD-7 source comments no longer claim no validated Russian
  version exists (Zolotareva 2023; Pfizer's official screeners).
- WHO-5 items are gender-neutral: «чувствовал(а)».
- "body fat" and "fat mass" both read «Жировая масса»; body fat is now
  «Процент жировой массы», which is what the two metrics measure.

Tests
- ru in the 13 locale tables, plus mood, onboarding, instruments, clinician
  view, status summary, describe screen, citation coverage and LOINC.
- i18n-no-dot-separator: the ru bundle is exempt from the dash rule (a spaced
  dash is Russian punctuation, not a fragment join); the middle dot still
  fails there.
- Two 800-line baselines raised by the 12 and 5 lines this change adds.

pnpm typecheck, pnpm openapi:check and the full suite (36 316 tests) pass.

docs/api/openapi.yaml

@@ -13235,6 +13235,7 @@ paths:
               - ko
               - nl
               - pt-BR
+              - ru
           description: Optional UI-locale override, any language the app ships; defaults to the session locale.
       responses:
         "200":
@@ -13274,6 +13275,7 @@ paths:
               - ko
               - nl
               - pt-BR
+              - ru
           description: Optional UI-locale override, any language the app ships; defaults to the session locale.
       responses:
         "200":
@@ -13313,6 +13315,7 @@ paths:
               - ko
               - nl
               - pt-BR
+              - ru
           description: Optional UI-locale override, any language the app ships; defaults to the session locale.
       responses:
         "200":
@@ -13352,6 +13355,7 @@ paths:
               - ko
               - nl
               - pt-BR
+              - ru
           description: Optional UI-locale override, any language the app ships; defaults to the session locale.
       responses:
         "200":
@@ -13391,6 +13395,7 @@ paths:
               - ko
               - nl
               - pt-BR
+              - ru
           description: Optional UI-locale override, any language the app ships; defaults to the session locale.
       responses:
         "200":
@@ -13431,6 +13436,7 @@ paths:
               - ko
               - nl
               - pt-BR
+              - ru
           description: Optional UI-locale override, any language the app ships; defaults to the session locale.
       responses:
         "200":
@@ -13533,6 +13539,7 @@ paths:
               - ko
               - nl
               - pt-BR
+              - ru
           description: Optional UI-locale override, any language the app ships; defaults to the session locale.
       responses:
         "200":
@@ -13585,6 +13592,7 @@ paths:
               - ko
               - nl
               - pt-BR
+              - ru
           description: Optional UI-locale override, any language the app ships; defaults to the session locale.
       responses:
         "200":
@@ -27962,6 +27970,7 @@ components:
             - ko
             - nl
             - pt-BR
+            - ru
         practiceName:
           type: string
           maxLength: 120
@@ -28676,6 +28685,7 @@ components:
                 - ko
                 - nl
                 - pt-BR
+                - ru
             - type: "null"
         timezone:
           type: string
@@ -30499,6 +30509,7 @@ components:
             - ko
             - nl
             - pt-BR
+            - ru
         today:
           description: "Optional override of the reference date used to resolve relative phrases (\"tomorrow\", \"next Monday\").
             Format: `YYYY-MM-DD`. Defaults to the account's own day in its time zone."
@@ -31468,6 +31479,7 @@ components:
             - ko
             - nl
             - pt-BR
+            - ru
           description: One of the interface locales this build ships.
       required:
         - locale
@@ -31510,6 +31522,7 @@ components:
             - ko
             - nl
             - pt-BR
+            - ru
         scope:
           type: object
           properties:
@@ -31681,6 +31694,7 @@ components:
             - ko
             - nl
             - pt-BR
+            - ru
         attachmentIds:
           minItems: 1
           maxItems: 5
@@ -35679,6 +35693,7 @@ components:
             - ko
             - nl
             - pt-BR
+            - ru
       required:
         - message
     InboundFactEditRequest:
@@ -37178,6 +37193,7 @@ components:
             - ko
             - nl
             - pt-BR
+            - ru
         timezone:
           type: string
           minLength: 1
@@ -37234,6 +37250,7 @@ components:
             - ko
             - nl
             - pt-BR
+            - ru
         timezone:
           type: string
           minLength: 1
@@ -37454,6 +37471,7 @@ components:
                 - ko
                 - nl
                 - pt-BR
+                - ru
             - type: "null"
         timezone:
           type: string
@@ -60477,6 +60495,7 @@ components:
                 - ko
                 - nl
                 - pt-BR
+                - ru
           required:
             - locale
           additionalProperties: false
@@ -89017,6 +89036,7 @@ components:
                 - ko
                 - nl
                 - pt-BR
+                - ru
             - type: "null"
         timezone:
           type: string