Engine v0.28.0

Changed: the Pipelines screens (#110)

Workflows. The search answers while you type: the server still searches
(the list is paginated), and the list is swapped under the box. State and
schedule are Segmented filters, each choice with its count. Tags are a popover
with a box that filters them, and two tags combine with AND (?tag=a&tag=b).
Each row draws its last 14 runs as squares linked to the runs, read in one
query for the page, and says its schedule in words for the shapes that are
certain (0 4 * * * → "every day at 04:00"); any other expression is shown
as written.

Workflow. The title is the slug, with its project, schedule in words and
Active/Paused above it, and the four numbers are one Stats strip. A workflow
with parameters runs from a "Run…" drawer with a preview of the payload; the
trigger is the same POST. With no script, the form shows in place.

Runs. The state filter counts each choice, each duration has a bar against
the page's longest, and a "Live" switch (off by default, remembered per
browser) refreshes the list every 5 s, washing the new runs. Nothing is
requested while the tab is hidden.

Run. A strip of phases under the header -- scheduled or triggered, how late
it started (from the slot, like delay_seconds), how long it ran, how it
ended -- refreshing with the rest of the live head.

No migration. No configuration changes. On a large history, runs would
benefit from an index on (workflow_slug, criado_em) (#109).