fix(blog): improve blog tab visibility and add help text

Changes blog tab visibility check from generic IsWriter to specific CanWrite permission for code unit. Adds help text to blog and subscription settings explaining behavior and access requirements.

options/locale/locale_en-US.json

@@ -2005,6 +2005,7 @@
   "repo.settings.blog": "Blog",
   "repo.settings.blog.enable": "Enable Blog",
   "repo.settings.blog.enable_desc": "Allow blog posts to be created and published from this repository.",
+  "repo.settings.blog.enable_help": "When enabled, repo members with write access can create, edit, and publish blog posts. Subscribers and watchers will be notified on publish.",
   "repo.settings.blog.saved": "Blog settings saved.",
   "repo.wiki": "Wiki",
   "repo.wiki.welcome": "Welcome to the Wiki.",
@@ -4136,6 +4137,7 @@
   "repo.settings.subscriptions.products": "Products",
   "repo.settings.subscriptions.clients": "Clients",
   "repo.settings.subscriptions.enable": "Enable paid subscriptions",
+  "repo.settings.subscriptions.enable_help": "When enabled, code access (source view, clone, archive) will require an active subscription. Issues and releases remain accessible per the repository's visibility settings.",
   "repo.settings.subscriptions.enable_desc": "When enabled, code access (source view, clone, archive) will require an active subscription. Issues and releases remain accessible per the repository's visibility settings.",
   "repo.settings.subscriptions.enabled": "Subscriptions are enabled for this repository.",
   "repo.settings.subscriptions.disabled": "Subscriptions are disabled.",

templates/repo/header.tmpl

@@ -214,7 +214,7 @@
 					{{end}}
 
 					{{if and .Repository.BlogEnabled (ctx.RootData.SystemConfig.Theme.EnableBlogs.Value ctx)}}
-						{{if or .IsWriter (gt .BlogPostCount 0)}}
+						{{if or (.Permission.CanWrite ctx.Consts.RepoUnitTypeCode) (gt .BlogPostCount 0)}}
 						<a class="{{if .PageIsRepoBlog}}active {{end}}item" href="{{.RepoLink}}/blog">
 							{{svg "octicon-note"}} {{ctx.Locale.Tr "repo.blog"}}
 							{{if gt .BlogPostCount 0}}<span class="ui small label">{{.BlogPostCount}}</span>{{end}}

templates/repo/settings/options.tmpl

@@ -361,6 +361,7 @@
 						<input name="enable_blog" type="checkbox" {{if .Repository.BlogEnabled}}checked{{end}}>
 						<label>{{ctx.Locale.Tr "repo.settings.blog.enable"}}</label>
 					</div>
+					<p class="help">{{ctx.Locale.Tr "repo.settings.blog.enable_help"}}</p>
 				</div>
 				{{end}}