Add custom fonts: upload WOFF2/WOFF/TTF/OTF files and pick them on the Design tab

Fonts become a file kind of their own (sniffed from the bytes like images,
served inline from /media), and the theme gets custom_font and
custom_heading_font: a chosen file is declared as @font-face and put first
in the stack, the built-in Font / Heading font choice behind it as the
fallback, so there is no "custom" enum value and no invalid state. The
pickers are plain selects with an upload input, no script. Fonts uploaded
before this are reclassified by the migration.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Sd8UPWrvyYCLj97JexNw3A

1 files changed, 17 insertions, 11 deletions

diff --git a/internal/web/handlers_design.go b/internal/web/handlers_design.go
index acc7569..792dcdc 100644
--- a/internal/web/handlers_design.go
+++ b/internal/web/handlers_design.go
@@ -13,7 +13,8 @@ import (
 // the menu — saved in one go.
 
 // recentImages is how many library images the pickers list up front; the
-// rest are fetched by the script's library panel, page by page.
+// rest are fetched by the script's library panel, page by page. The font
+// pickers list as many, with no panel behind them: a blog has a few fonts.
 const recentImages = 48
 
 // designView is the state the design page shows: what the database holds, or
@@ -71,13 +72,17 @@ func (s *Server) designData(r *http.Request, v designView) (map[string]any, erro
 	if err != nil {
 		return nil, err
 	}
-	// The pickers list the recent images; a chosen one older than that still
+	fonts, _, err := bs.ListFiles(r.Context(), "font", "", recentImages, 0)
+	if err != nil {
+		return nil, err
+	}
+	// The pickers list the recent files; a chosen one older than that still
 	// needs its name for the select.
 	names := map[string]string{}
-	for _, f := range images {
+	for _, f := range append(images, fonts...) {
 		names[f.ID.String()] = f.Filename
 	}
-	for _, id := range []string{v.Theme.BgImage, v.Theme.HeaderImage, v.Theme.Logo, v.Theme.Favicon} {
+	for _, id := range []string{v.Theme.BgImage, v.Theme.HeaderImage, v.Theme.Logo, v.Theme.Favicon, v.Theme.CustomFont, v.Theme.CustomHeadingFont} {
 		if id == "" || names[id] != "" {
 			continue
 		}
@@ -115,7 +120,7 @@ func (s *Server) designData(r *http.Request, v designView) (map[string]any, erro
 		"templates": templates, "pageItem": store.MenuItem{PageID: &pageID}, "linkItem": store.MenuItem{},
 		"kinds": moduleKinds, "names": moduleNames, "areaNames": areaNames, "single": singleModuleAreas,
 		"counts": []int{3, 5, 8, 10, 15, 20}, "tagCounts": []int{5, 10, 20, 30, 50}, "perPage": postsPerPageChoices,
-		"images": images, "imageNames": names, "imageCount": imageCount, "presets": Presets(), "today": time.Now(),
+		"images": images, "fonts": fonts, "imageNames": names, "imageCount": imageCount, "presets": Presets(), "today": time.Now(),
 	}, nil
 }
 
@@ -164,16 +169,17 @@ func (s *Server) handleDesign(w http.ResponseWriter, r *http.Request) {
 	// Optional direct uploads from the pickers. One that is stored stays
 	// chosen in the form even when something else is rejected.
 	for _, u := range []struct {
-		field string
-		dst   *string
-	}{{"bg_image_file", &v.Theme.BgImage}, {"header_image_file", &v.Theme.HeaderImage}, {"logo_file", &v.Theme.Logo}, {"favicon_file", &v.Theme.Favicon}} {
-		img, err := s.readUpload(r, u.field, true)
+		field, kind string
+		dst         *string
+	}{{"bg_image_file", "image", &v.Theme.BgImage}, {"header_image_file", "image", &v.Theme.HeaderImage}, {"logo_file", "image", &v.Theme.Logo}, {"favicon_file", "image", &v.Theme.Favicon},
+		{"custom_font_file", "font", &v.Theme.CustomFont}, {"custom_heading_font_file", "font", &v.Theme.CustomHeadingFont}} {
+		f, err := s.readUpload(r, u.field, u.kind)
 		if err != nil {
 			note(err)
 			continue
 		}
-		if img != nil {
-			*u.dst = img.ID.String()
+		if f != nil {
+			*u.dst = f.ID.String()
 		}
 	}
 	if problem != nil {