Add announcements: blog-wide notices on every page and post

A blog can have any number of announcements ("sections" in the schema):
a book club's next meeting, this month's pick, a holiday closure. Each
has a placement (above or below the posts, or under the menu when the
menu is a left sidebar), a look (highlighted, warning, plain), an order,
and an on/off switch so recurring notices can be kept around while hidden.

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

1 files changed, 19 insertions, 0 deletions

diff --git a/internal/db/migrations/00002_sections.sql b/internal/db/migrations/00002_sections.sql
new file mode 100644
index 0000000..388cb17
--- /dev/null
+++ b/internal/db/migrations/00002_sections.sql
@@ -0,0 +1,19 @@
+-- +goose Up
+-- Announcements: blog-wide notices shown on every page and post.
+CREATE TABLE sections (
+    id          bigserial PRIMARY KEY,
+    blog_id     bigint NOT NULL REFERENCES blogs(id) ON DELETE CASCADE,
+    title       text NOT NULL DEFAULT '',
+    body_md     text NOT NULL DEFAULT '',
+    body_html   text NOT NULL DEFAULT '',
+    placement   text NOT NULL DEFAULT 'above' CHECK (placement IN ('above', 'below', 'sidebar')),
+    style       text NOT NULL DEFAULT 'note' CHECK (style IN ('plain', 'note', 'warning')),
+    enabled     boolean NOT NULL DEFAULT true,
+    sort_order  integer NOT NULL DEFAULT 0,
+    created_at  timestamptz NOT NULL DEFAULT now(),
+    updated_at  timestamptz NOT NULL DEFAULT now()
+);
+CREATE INDEX sections_blog ON sections (blog_id, sort_order, id);
+
+-- +goose Down
+DROP TABLE sections;