Add Twitter video support and use sql.Null[T] for nullable columns

- Store Twitter video URLs in embed_video_url column instead of downloading
- Play videos directly from Twitter's CDN in <video> element
- Fix Twitter API parsing (content_type/url fields)
- Strip t.co URLs from tweet text descriptions
- Use sql.Null[T] generic type for nullable DB columns
- Add Nullable[T] and Ptr[T] helper functions
- Add play indicator overlay for video items in grid
- Add migration for embed_video_url column

internal/handlers/home.go

@@ -3,6 +3,7 @@ package handlers
 import (
 	"context"
 	"net/http"
+	"strings"
 	"time"
 
 	"git.soup.land/soup/sxgo/ssr"
@@ -29,6 +30,7 @@ type homeItem struct {
 	Tags        []string
 	ThumbnailID *int64
 	MediaID     *int64
+	HasVideo    bool
 }
 
 func (h homeContent) Render(sw *ssr.Writer) error {
@@ -57,8 +59,10 @@ func (h homeContent) Render(sw *ssr.Writer) error {
 			</div>
 			{{else if .ThumbnailID}}
 			<img src="/media/{{.ThumbnailID}}" alt="{{if .Title}}{{.Title}}{{else}}Image{{end}}" loading="lazy">
+			{{if or .HasVideo (eq .ItemType "video")}}<div class="play-indicator">▶</div>{{end}}
 			{{else if .MediaID}}
 			<img src="/media/{{.MediaID}}" alt="{{if .Title}}{{.Title}}{{else}}Image{{end}}" loading="lazy">
+			{{if or .HasVideo (eq .ItemType "video")}}<div class="play-indicator">▶</div>{{end}}
 			{{else if eq .ItemType "embed"}}
 			<div class="embed-placeholder">
 				<span>▶</span>
@@ -160,11 +164,11 @@ func HandleHome(rc *RequestContext, w http.ResponseWriter, r *http.Request) erro
 	for _, it := range items {
 		hi := homeItem{
 			ID:          it.PubID,
-			Title:       it.Title,
-			Description: it.Description,
-			LinkURL:     it.LinkURL,
+			Title:       item.Ptr(it.Title),
+			Description: item.Ptr(it.Description),
+			LinkURL:     item.Ptr(it.LinkURL),
 			ItemType:    it.ItemType,
-			EmbedHTML:   it.EmbedHTML,
+			EmbedHTML:   item.Ptr(it.EmbedHTML),
 		}
 
 		// Get tags
@@ -187,9 +191,17 @@ func HandleHome(rc *RequestContext, w http.ResponseWriter, r *http.Request) erro
 				hi.ThumbnailID = &m.ID
 			} else if m.MediaType == "original" {
 				hi.MediaID = &m.ID
+				if strings.HasPrefix(m.ContentType, "video/") {
+					hi.HasVideo = true
+				}
 			}
 		}
 
+		// Also check for embed video URL
+		if it.EmbedVideoURL.Valid && it.EmbedVideoURL.V != "" {
+			hi.HasVideo = true
+		}
+
 		homeItems = append(homeItems, hi)
 	}