Make the post form's tag input a box with a folded list of chips

A checkbox per existing tag stops working once a blog has dozens of
them. The form is now one comma-separated box, prefilled with the
post's tags, and the blog's tags sit folded under it as chips; a small
script toggles a clicked chip in the box, and without it the chips are
a plain list to copy from.

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

1 files changed, 6 insertions, 4 deletions

diff --git a/AGENTS.md b/AGENTS.md
index 974fc10..18bc043 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -278,10 +278,12 @@ internal/web/         server.go (host router, middleware, render helpers)
   the URL (`/tag/<slug>`, `handleBlogTag`, published posts of every page,
   paginated) and the dedupe key — "Go" and "go" are one tag, the first
   spelling wins. `Post.Tags` rides along in `postCols` as two arrays.
-  The post form offers the blog's existing tags as checkboxes (`tag`) plus
-  a comma-separated `new_tags` box; `parseTags` normalises both into one
-  list (20 per post, 40 runes each; nothing slug-worthy → dropped) and
-  `SetPostTags` stores it after the post is saved. Tags no post carries
+  The post form is one comma-separated `tags` box (prefilled by
+  `tagsText`); the blog's existing tags sit folded under it as chips that
+  a small inline script toggles in the box (a plain list without JS).
+  `parseTags` normalises the box (20 per post, 40 runes each; nothing
+  slug-worthy → dropped) and `SetPostTags` stores it after the post is
+  saved. Tags no post carries
   are deleted (`deleteOrphanTags`, also after post/page deletion), so the
   form only lists tags in use. `TagCounts` counts published posts only:
   a tag on hidden posts alone shows nowhere public and its page is a 404.