Refactor text utility classes to Tailwind CSS (#36703)

Replace Fomantic/custom CSS text utility classes with their Tailwind
equivalents:

- `.text.<color>` compound classes → `tw-text-<color>` classes
- `.text.small` (`font-size: 0.75em`) → `tw-text-xs` (11px)
- `.text.truncate` (`overflow-x: hidden; text-overflow: ellipsis;
white-space: nowrap; display: inline-block`) → `tw-inline-block
tw-truncate`

Remove the now-unused CSS rules from `base.css` and `dashboard.css`.

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Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

templates/repo/actions/workflow_dispatch_inputs.tmpl

@@ -40,7 +40,7 @@
 {{range .workflows}}
 	{{if and .ErrMsg (eq .Entry.Name $.CurWorkflow)}}
 		<div class="ui field">
-			<div>{{svg "octicon-alert" 16 "text red"}} {{.ErrMsg}}</div>
+			<div>{{svg "octicon-alert" 16 "tw-text-red"}} {{.ErrMsg}}</div>
 		</div>
 	{{end}}
 {{end}}