feat(watchlist): stop a title being marked watched before it is out

[Isma-L154]

What

A saved title that has not been released no longer offers Watched. Where the button was, the card says when it lands.

Released	✓ Watched
Out Sep 9	🕐 Out Sep 9 (amber, not a control)
Premieres Nov 5	🕐 Premieres Nov 5
No date at all	✓ Watched — still offered, see below
Already watched	↻ Unwatch — never taken away

Why not a disabled button

A greyed control still reads as an action you are failing to perform, and it invites the tap that does nothing. A date answers the question the button was standing in front of. The remove button stays beside it: changing your mind about waiting for something is not the same as claiming to have seen it.

This is not a new kind of restriction — the app already refuses to tick a show past its aired seasons. It is the same rule for the other half of the library.

Only a confirmed future date refuses

A title TMDB holds no date for is still tickable. That state means two opposite things: a production announced years out, and an obscure catalogue title nobody has dated. Refusing on it would lock a film somebody watched decades ago on the strength of a missing field. Not knowing when something came out is not knowing that it has not.

Un-watching is never blocked, so a row saved before this rule — or one whose date has since moved outwards — is never stranded claiming something its owner cannot take back.

Enforced in the action as well as the card, since the card is a form and a form body can be written by hand.

The part that makes the block safe

A film's release date was snapshotted on save and never revised anywhere. Blocking on it would mean a studio moving a release forward left the card refusing forever, with removing and re-saving the title the only way out.

So the read path now re-asks about titles that have not come out, the way it already re-asks about seasons — only those rows, so it converges to nothing for the rest of a list. That also fixes two places the stale date was already wrong before this PR: the Upcoming grouping, and the calendar feed, which was publishing slipped premieres into people's calendars as appointments for a night with nothing on.

Found while driving it in a browser

• In theaters In 3 days read like a typo. The line takes the date and leaves the countdown to the poster badge directly above it — one glance says how soon, the line underneath says what and when.
• A far-off date carries its year, and Premieres Sep 30, 2028 needs 126px in a 109px tile. It wraps rather than truncating, because a cut year is the part worth reading; the slot was already 44px tall for the button it replaced, so the row of cards stays level. Pinned by a measuring test rather than left to the next person to rediscover.
• Coming Soon called a film's release a premiere. Pre-existing, but it only became visible once the card above it started saying "Out" — the caption was contradicting its own card.

Verified

• npm run check — 0 errors, 0 warnings; npm run lint clean
• 480 unit tests pass, 8 files touched, 3 new suites: the rule and its wording, the action's refusal, and the date refresh against a real database (moved forward, slipped, withdrawn, unreachable, unchanged, and the batch cap)
• New WatchlistCard.svelte.spec.ts measures real boxes in a browser: which control each state gets, and that the longest possible label renders in full inside the slot
• 17 e2e pass
• Driven by hand against a seeded database covering released / imminent / far-future / undated / unpremiered / already-watched. A seeded title whose date was 400 days out self-corrected to 2024 on load and unlocked its own card, which is the refresh working end to end against the live API. A forged POST on an unreleased title came back 400 “Dune Part Three” isn't out yet. with the row untouched; un-watching a future-dated row still succeeded.