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`.

---------

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

templates/repo/release/list.tmpl

@@ -44,7 +44,7 @@
 								{{end}}
 							</div>
 						</div>
-						<p class="text grey">
+						<p class="tw-text-text-light">
 							<span class="author">
 							{{if $release.OriginalAuthor}}
 								{{svg (MigrationIcon $release.Repo.GetOriginalURLHostname) 20 "tw-mr-1"}}{{$release.OriginalAuthor}}

templates/repo/release/new.tmpl

@@ -83,7 +83,7 @@
 					<div class="flex-text-block tw-flex-1">
 						<input name="attachment-edit-{{.UUID}}" class="tw-max-w-[48em]" required value="{{.Name}}">
 						<input name="attachment-del-{{.UUID}}" type="hidden" value="false">
-						<span class="text grey tw-flex-shrink-0">{{.Size | FileSize}}</span>
+						<span class="tw-text-text-light tw-flex-shrink-0">{{.Size | FileSize}}</span>
 						<span data-tooltip-content="{{ctx.Locale.Tr "repo.release.download_count" (ctx.Locale.PrettyNumber .DownloadCount)}}">
 							{{svg "octicon-info"}}
 						</span>