fix(mcp): localize the OAuth re-authorization prompt (#1270)

* fix(mcp): localize the OAuth re-authorization prompt

The non-interactive OAuth provider threw a hard-coded English message that
still pointed at the old "Test" button. Route it through i18n, reference the
"Connect" button, and add translations for all locales.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

* fix(mcp): use i18next t for the OAuth re-authorization prompt

Importing the renderer i18n entry from the MCP package pulls its full
initialization into every module that touches OAuth, which breaks suites
that stub i18next without a default export. Use the bound t from i18next
like the stores do.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

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Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>
(cherry picked from commit 77581a4955e4d843f7c8d5ba4a85da52829ec3dc)

(cherry picked from pro commit 3ca2c15b5b377448e9eb2f635670575a7f46927e)