fix(deps): update dependency i18next to v26

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
i18next (source)	^25.7.4 → ^26.0.0
i18next (source)	^25.7.4 → ^26.0.0

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Release Notes

i18next/i18next (i18next)

v26.0.3

Compare Source

• fix(types): addResourceBundle now accepts an optional 6th options parameter ({ silent?: boolean; skipCopy?: boolean }) matching the runtime API 2419

v26.0.2

Compare Source

• fix(types): t("key", {} as TOptions) no longer produces a type error — the context constraint now bypasses strict checking when context is unknown (e.g. from TOptions) 2418

v26.0.1

Compare Source

• fix: Formatter no longer crashes when alwaysFormat is true and no format specifier is present (format is undefined)
• fix: Formatter now returns undefined/null values as-is instead of producing NaN when the value is missing

v26.0.0

Compare Source

This is a major breaking release:

Breaking Changes

• Remove deprecated initImmediate option — the backward-compatibility mapping from initImmediate to initAsync (introduced in v24) has been removed. Use initAsync instead.
• Remove legacy interpolation.format function — the old monolithic format function (interpolation: { format: (value, format, lng) => ... }) is no longer supported. The built-in Formatter (or a custom Formatter module via .use()) is now always used. Migrate to the new formatting approach using i18next.services.formatter.add() or .addCached() for custom formatters.
• Remove console support notice — the console support notice introduced in v25.8.0 has been removed, along with the showSupportNotice option and all related internal suppression logic (globalThis.__i18next_supportNoticeShown, I18NEXT_NO_SUPPORT_NOTICE env var). See our blog post for the full story.
• Remove simplifyPluralSuffix option — this option was unused by the core PluralResolver (which relies entirely on Intl.PluralRules). It only had an effect in the old v1/v2/v3 compatibility layer. The v4 test compatibility layer now defaults to true internally.
• Remove deprecated @babel/polyfill from devDependencies.

Improvements

• Code modernization across all source files:
  • Replace indexOf() > -1 / indexOf() < 0 with .includes() (~40+ occurrences)
  • Replace indexOf() === 0 with .startsWith() where appropriate
  • Replace var with const, '' + object with String(object), .substring() with .slice()
  • Replace .apply(observer, [event, ...args]) with direct call observer(event, ...args)
  • Remove unnecessary .call(this, ...) in BackendConnector retry logic
  • Fix array-callback-return in LanguageUtils getBestMatchFromCodes
  • Clean up all stale eslint-disable comments from source files
• EventEmitter: add once() method for one-time event subscriptions
• Memory leak fix: move module-level checkedLoadedFor cache to Translator instance, preventing cross-instance state leakage
• TypeScript: fix BackendModule generic parameter naming inconsistency between CJS and ESM type definitions
• TypeScript: add once() method to i18n and ResourceStore type interfaces
• ESLint 9: migrate from ESLint 8 (airbnb-base) to ESLint 9 flat config with neostandard
• Vitest 4: upgrade from vitest 3 to vitest 4, migrate workspace files to test.projects config

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[github-actions]

🚨 PeerDependencies Change Detected 🚨

Your pull request includes modifications to peerDependencies in the following file(s):

❌ Invalid peerDependencies change in projects/core/package.json
-    "i18next": "^25.7.4",
+    "i18next": "^26.0.0",

Please note: Changes to peerDependencies are restricted and only permitted during framework update releases, as they may introduce breaking changes for customer's applications.
If you believe this change is necessary, please reach out to the Asterix team for further assistance.