fix(webapp): set min-width for task filter dropdown when text is truncated

Changed the SelectPopover min-width from 0 to 360px to ensure the dropdown
always has adequate space for displaying task names with middle truncation.
This prevents the dropdown from becoming too narrow when long task names
are present.

Slack thread: https://triggerdotdev.slack.com/archives/C032WA2S43F/p1769451219774789?thread_ts=1769436524.157219&cid=C032WA2S43F

https://claude.ai/code/session_01KrFXrmK7jz9sWTcS8pMtXL

Author: claude

apps/webapp/app/components/runs/v3/RunFilters.tsx

@@ -635,7 +635,7 @@ function TasksDropdown({
     <SelectProvider value={values("tasks")} setValue={handleChange} virtualFocus={true}>
       {trigger}
       <SelectPopover
-        className="min-w-0 max-w-[min(360px,var(--popover-available-width))]"
+        className="min-w-[360px] max-w-[min(360px,var(--popover-available-width))]"
         hideOnEscape={() => {
           if (onClose) {
             onClose();