[feature] Add opt-in RSS feed for account's latest Public posts (#897)

* start adding rss functionality

* add gorilla/feeds dependency

* first bash at building rss feed
still needs work, this is an interim commit

* tidy up a bit

* add publicOnly option to GetAccountLastPosted

* implement rss endpoint

* fix test

* add initial user docs for rss

* update rss logo

* docs update

* add rssFeed to frontend

* feed -> feed.rss

* enableRSS

* increase rss logo size a lil bit

* add rss toggle

* move emojify to text package

* fiddle with rss feed formatting

* add Text field to test statuses

* move status to rss item to typeconverter

* update bun schema for enablerss

* simplify 304 checking

* assume account not rss

* update tests

* update swagger docs

* allow more characters in title, trim nicer

* update last posted to be more consistent

internal/typeutils/internaltofrontend.go

@@ -105,7 +105,7 @@ func (c *converter) AccountToAPIAccountPublic(ctx context.Context, a *gtsmodel.A
 
 	// check when the last status was
 	var lastStatusAt string
-	lastPosted, err := c.db.GetAccountLastPosted(ctx, a.ID)
+	lastPosted, err := c.db.GetAccountLastPosted(ctx, a.ID, false)
 	if err == nil && !lastPosted.IsZero() {
 		lastStatusAt = util.FormatISO8601(lastPosted)
 	}
@@ -219,6 +219,7 @@ func (c *converter) AccountToAPIAccountPublic(ctx context.Context, a *gtsmodel.A
 		Fields:         fields,
 		Suspended:      suspended,
 		CustomCSS:      a.CustomCSS,
+		EnableRSS:      *a.EnableRSS,
 	}
 
 	c.ensureAvatar(accountFrontend)