feat(gmail): take the star off a mail once it has become a task

A starred Gmail message became a task and kept its star, so a starred inbox only
grew — the IMAP side has always unflagged what it imports, and Gmail could not,
because the scope was gmail.readonly. This gives Gmail the same one write: after
the task is made, the STARRED label comes off the message, in one batchModify for
the whole sweep. Nothing else is touched — not the body, not other labels, and a
label trigger's label stays where it is, since that label is the person's own.

The scope goes from gmail.readonly to gmail.modify, which is the narrowest scope
Google offers that can remove a label. An existing connection keeps working on its
old read-only grant — the sync still reads, the unstar is a best-effort 403 that is
logged, not fatal — and starts clearing stars once the account is reconnected and
the new grant is in place. It self-heals: a mail that could not be unstarred stays
starred, stays in the next query, and is tried again.

The consent screen now asks for more than it used to; the settings copy, the docs
and the scope table all say modify rather than read-only in the same change.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

web/src/lib/locales/da.js

@@ -660,7 +660,7 @@ export const da = {
 	// --- settings: integrations --------------------------------------------------------
 	'int.mailboxes': 'Postkasser',
 	'int.mailboxesHint':
-		'Flag en mail i iCloud, Fastmail eller enhver anden udbyder, og den bliver en opgave. Én vej: fjerner du flaget, sker der ikke noget med opgaven. Office 365 kan ikke bruges her — Microsoft har lukket for kodeord på IMAP.',
+		'Flag en mail i iCloud, Fastmail eller enhver anden udbyder, og den bliver en opgave — flaget fjernes, når opgaven er oprettet. Kun én vej: gør du selv noget ved mailen bagefter, sker der ikke noget med opgaven. Office 365 kan ikke bruges her — Microsoft har lukket for kodeord på IMAP.',
 	'int.addMailbox': 'Tilføj en postkasse',
 	'int.host': 'IMAP-server',
 	'int.username': 'Brugernavn',
@@ -676,7 +676,7 @@ export const da = {
 	'int.fetching': 'Henter …',
 	'int.gmail': 'Gmail',
 	'int.gmailHint':
-		'Stjernemarkér en mail, eller giv den en etiket, og den bliver en opgave. Envejs: at fjerne stjernen gør ikke noget ved opgaven.',
+		'Stjernemarkér en mail, eller giv den en etiket, og den bliver en opgave — stjernen fjernes så (en etiket bliver, hvor den er). Det du selv gør ved mailen bagefter, ændrer ikke opgaven.',
 	'int.connectGmail': 'Forbind Gmail',
 	'int.fromEnv':
 		'Klienten er sat i miljøet (VERDANDE_GMAIL_CLIENT_ID), så den kan ikke ændres her. Det er med vilje: en værdi i runens manifest er en beslutning, der bliver anvendt igen ved hver genstart, og en formular, der kunne overskrive den, ville gøre manifestet til en løgn.',

web/src/lib/locales/en.js

@@ -656,7 +656,7 @@ export const en = {
 	// --- settings: integrations --------------------------------------------------------
 	'int.mailboxes': 'Mailboxes',
 	'int.mailboxesHint':
-		'Flag an email in iCloud, Fastmail or any other provider and it becomes a task. One way: removing the flag does nothing to the task. Office 365 cannot be used here — Microsoft has closed IMAP to passwords.',
+		'Flag an email in iCloud, Fastmail or any other provider and it becomes a task — the flag comes off once it has. One way only: what you do to the mail afterwards does not change the task. Office 365 cannot be used here — Microsoft has closed IMAP to passwords.',
 	'int.addMailbox': 'Add a mailbox',
 	'int.host': 'IMAP server',
 	'int.username': 'Username',
@@ -672,7 +672,7 @@ export const en = {
 	'int.fetching': 'Fetching …',
 	'int.gmail': 'Gmail',
 	'int.gmailHint':
-		'Star an email, or give it a label, and it becomes a task. One way: removing the star does nothing to the task.',
+		'Star an email, or give it a label, and it becomes a task — the star then comes off (a label stays where it is). What you do to the mail afterwards does not change the task.',
 	'int.connectGmail': 'Connect Gmail',
 	'int.fromEnv':
 		'The client is set in the environment (VERDANDE_GMAIL_CLIENT_ID), so it cannot be changed here. That is deliberate: a value in the Rune’s manifest is a decision reapplied on every restart, and a form that could overwrite it would make the manifest a lie.',

web/src/routes/indstillinger/integrationer/+page.svelte

@@ -423,7 +423,7 @@
 
 		<!-- The registration behind the button, for whoever can do something about
 		     it. Google issues no Gmail access to an unregistered client, and
-		     gmail.readonly is a restricted scope — so this step cannot be skipped by
+		     gmail.modify is a restricted scope — so this step cannot be skipped by
 		     any app. It can stop requiring a redeploy, which is what this is. -->
 		{#if app.user?.is_admin && client}
 			{#if client.from_env}