fix(frontend): multilingual fixes from the round-1 end-to-end run (D-07, D-12, D-19, D-21)

[navidshad]

What

Five small fixes found by the round-1 end-to-end run against a local server (local MongoDB, no AI or payment keys).

1. Your progress mixed languages. The page header says "Your German progress", but the recent bundles, the bundle count and the phrase count read every language. They now use the active language only (languageQuery(), as the Bundles page does). This also stops the dashboard from adding to the server's missing_language_read count, which is meant for old clients.
2. "Back to the steps" in the chat test went to step 1. The spec says the way out is back to step 2. The link now carries step=2 and Add a language opens on step 2 with the language still picked.
3. Today's starter pack card did not show progress after marking chunks and going back to Today (the state was refreshed only when the pack was done). The page now refreshes the language state when you leave it, so the card says "20 of 150 heard · Continue".
4. Persian translations in a bundle were shown left to right. The phrase and translation boxes now have dir="auto", so each gets its own direction.
5. English help in the chat test was put in a right-to-left run for a Persian speaker when the Coach falls back to its fixed questions (their help lines are English), so it read "?What is your name". Help text with no right-to-left letters now lets the browser pick the direction (runLanguage() in utils/languages.ts).

Rows: D-07, D-12, D-19, D-21.

How it was tested

• Vitest: new runLanguage tests; the whole unit suite passes (121).
• Playwright (hermetic multilingual.spec.ts): six new tests, one per fix (two for the help direction); all 21 pass locally on chromium.
• Live: the same flows against a local server and the built frontend, with screenshots.

🤖 Generated with Claude Code

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