feat(filter): persist board filters (saved views + default view)

[heinrich-toews]

• Resolves: Save filters #2861
• Target version: main

Summary

This changeset implements the requested "Save filters" feature by letting users save deck board filters as named views and re-apply them later, plus the ability to set one saved view as the default for a board.

Saved board views

• New BoardView entity, mapper, service and OCS API controller.
• CRUD routes under deck/api/v1.0/views (index/create/update/delete).
• The filter popover in Controls.vue lets you save the active filter as a named view and re-apply it.

Default view

• ConfigService::defaultBoardView persisted per user + board.
• New picker in DeckAppSettings.vue (per-user Default settings) to choose the default view.
• When opening a board, the default view is applied automatically; tags are only applied where they match the current board.

Migration

• Version11003Date20260821120000 creates oc_deck_board_views.
• Numbered 11003, safely above the current latest 11002.

Testing steps

1. Apply this branch and run occ upgrade (or it runs via the updater).
2. Open a board, set a filter (label/priority/tag/assignee/…), choose Save as view and name it.
3. Confirm the view appears in the filter popover, re-applies when clicked, and can be edited/deleted.
4. Go to Deck settings → Default, pick the saved view as the default.
5. Open a different board / reload: the default view is applied automatically (tags only where they match).

Note: l10n/* is intentionally not included per the project's Transifex workflow — translations are managed upstream.

[heinrich-toews]

Hi — this is a first contribution from a fork, so the GitHub Actions workflows are pending approval. Could a maintainer approve the workflow runs so CI can execute? Thanks!