Feature(template-gallery): add server-side pagination

[Musicminion]

• 9 templates per page, fetched page by page instead of loading the whole list
• backend: /api/templates takes page/pageSize/q (search), sorts and paginates in mongo
• frontend: port the upstream gallery pagination bar, move search onto its own row, center the category header, right-align the sort buttons

Description

Related issues / Pull Requests

Docs

Upgrading to Ayakaleaf Pro 6.3: Template Gallery indexes (optional)

The gallery now pages, sorts and searches in MongoDB. It works without any preparation; with thousands of templates, add these indexes to keep it fast (safe to re-run, mongo/sharelatex = your container and database names):

docker exec mongo mongosh sharelatex --quiet --eval '
db.templates.createIndex({category:1,lastUpdated:-1},{name:"category_1_lastUpdated_-1",background:true});
db.templates.createIndex({lastUpdated:-1},{name:"lastUpdated_-1",background:true});
db.templates.createIndex({category:1,name:1},{name:"category_1_name_1_ci",collation:{locale:"en",strength:2},background:true});
db.templates.createIndex({name:1},{name:"name_1_ci",collation:{locale:"en",strength:2},background:true});
'

Keep the collation on the two *_ci indexes as written — the gallery
queries with the same collation and MongoDB only uses a matching index.

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[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Ignore responses from superseded gallery requests

When page, sort, or debounced search parameters change before an earlier request finishes, every response still updates the same state. A slower obsolete request can therefore overwrite the latest response, leaving (for example) page 2's templates displayed while the pagination marks page 3 as current. Track the latest request or abort superseded requests before applying their results.

Useful? React with 👍 / 👎.

[chatgpt-codex-connector]

Add the indexes referenced by the paginated query

The referenced UPGRADE-6.3.md does not exist anywhere in the repository, and the TemplateSchema defines no corresponding indexes. Consequently, both { lastUpdated, _id } and collation-aware { name, _id } sorts remain blocking sorts over the complete matching collection before skip and limit are applied, undermining server-side pagination and potentially spilling or failing on large galleries. Ship explicit operator upgrade instructions or migrations for the required compound indexes.

Useful? React with 👍 / 👎.

[chatgpt-codex-connector]

Translate the visible pagination labels

For every non-English locale, the new controls still visibly render the English words First, Prev, Next, and Last; only their screen-reader labels use translations. This regresses the localized gallery UI, so the visible labels should also use the existing i18n keys.

Useful? React with 👍 / 👎.