feat(FN-4081): keep mobile timestamps inline in task detail modal

FN-4081 keeps task detail timestamps inline on mobile (no collapsible "more" row), with accompanying docs updates and a changeset for `@runfusion/fusion`. A test contract was updated to match the responsive layout change.

Fusion-Task-Id: FN-4081

docs/dashboard-guide.md

@@ -427,7 +427,7 @@ Inspect task definition, logs, review feedback, comments, documents, workflow ou
 - The priority chip in task metadata is an inline picker: you can change priority directly without entering full edit mode.
 - Execution mode has a read-mode inline lightning-bolt toggle for Fast mode on/off without opening the full edit form.
 - These two metadata controls share matched sizing/alignment in read mode (including mobile wrapping) so they behave like a single polished control group.
-- Task metadata also shows compact `Created` / `Updated` timestamps: recent values render as relative time (`just now`, `Xm`, `Xh`, `Xd`) and older values switch to short month/day dates; on desktop these stay grouped on one row, with a mobile-stacked layout for readability.
+- Task metadata also shows compact `Created` / `Updated` timestamps: recent values render as relative time (`just now`, `Xm`, `Xh`, `Xd`) and older values switch to short month/day dates; these stay grouped on one row across desktop and mobile widths for a compact metadata layout.
 - Eligible existing tasks (triage, todo, in-progress, in-review) expose a **GitHub tracking** section directly in Task Detail, even when tracking is currently disabled.
 - The GitHub tracking section now defaults to a compact summary row; use the disclosure arrow to expand linked-issue details plus tracking edit controls.
 - In shared task edit/create forms, GitHub Tracking appears at the bottom of **More options**, after **Workflow Steps**.