New /issues route: a sortable, filterable table over open issues across
every repo that has one -- repo picker (default: no filter, every repo
combined), hide-blocked toggle, and a label multi-select, consuming
swarm-controller's GET /api/repos + GET /api/issue-report / GET
/api/repos/{org}/{repo}/issue-report (see hyperhive#3831 for the row
shape). blocked and depended_on_by_count arrive pre-resolved per row --
this page does no dependency-graph walking of its own, just sort/filter
over what it's given. Default sort is depended_on_by_count descending,
matching mara's framing of the report's headline ordering.
Widened Table's TableColumn.header from string to ComponentChildren so
a column can carry a real clickable sort-toggle button instead of
forking a second table primitive for this one page.
e815c7cb5c