Drop the single-database split and re-baseline the control migrations

Every deployment has been through the per-blog split, so the code that
performed it (split.go, control migrations 00002–00007) is dead weight, and a
fresh install replaying six migrations only to drop the tables again was
silly. The control chain is now a single 00001_init.sql with the final users
and blogs shape, matching the blog chain.

Goose ignores versions recorded in the database that no longer exist in the
source, but refuses a future migration numbered below the database's highest
version. Databases that went through the split therefore need
`DELETE FROM goose_db_version WHERE version_id > 1` once; README and
AGENTS.md say so.

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

6 files changed, 6 insertions, 158 deletions

diff --git a/internal/db/migrations/control/00001_init.sql b/internal/db/migrations/control/00001_init.sql
index e27dad4..0b26b37 100644
--- a/internal/db/migrations/control/00001_init.sql
+++ b/internal/db/migrations/control/00001_init.sql
@@ -1,4 +1,6 @@
 -- +goose Up
+-- The control database: accounts and the list of blogs. Everything a blog
+-- contains lives in its own database (see migrations/blog).
 CREATE TABLE users (
     id             bigserial PRIMARY KEY,
     username       text NOT NULL UNIQUE,
@@ -9,60 +11,15 @@ CREATE TABLE users (
     created_at     timestamptz NOT NULL DEFAULT now()
 );
 
+-- "blog_" + subdomain must fit a 63-char Postgres identifier, hence 58.
 CREATE TABLE blogs (
     id          bigserial PRIMARY KEY,
     owner_id    bigint NOT NULL UNIQUE REFERENCES users(id) ON DELETE CASCADE,
-    subdomain   text NOT NULL UNIQUE CHECK (subdomain ~ '^[a-z0-9](-?[a-z0-9]){0,62}$'),
-    title       text NOT NULL,
-    tagline     text NOT NULL DEFAULT '',
-    theme       jsonb NOT NULL DEFAULT '{}'::jsonb,
-    created_at  timestamptz NOT NULL DEFAULT now(),
-    updated_at  timestamptz NOT NULL DEFAULT now()
+    subdomain   text NOT NULL UNIQUE CHECK (subdomain ~ '^[a-z0-9](-?[a-z0-9]){0,57}$'),
+    db_name     text NOT NULL UNIQUE,
+    created_at  timestamptz NOT NULL DEFAULT now()
 );
 
-CREATE TABLE pages (
-    id           bigserial PRIMARY KEY,
-    blog_id      bigint NOT NULL REFERENCES blogs(id) ON DELETE CASCADE,
-    slug         text NOT NULL,
-    title        text NOT NULL,
-    intro_md     text NOT NULL DEFAULT '',
-    intro_html   text NOT NULL DEFAULT '',
-    nav_order    integer NOT NULL DEFAULT 0,
-    show_in_nav  boolean NOT NULL DEFAULT true,
-    is_home      boolean NOT NULL DEFAULT false,
-    created_at   timestamptz NOT NULL DEFAULT now(),
-    UNIQUE (blog_id, slug)
-);
-CREATE UNIQUE INDEX pages_one_home_per_blog ON pages (blog_id) WHERE is_home;
-
-CREATE TABLE posts (
-    id          bigserial PRIMARY KEY,
-    page_id     bigint NOT NULL REFERENCES pages(id) ON DELETE CASCADE,
-    slug        text NOT NULL,
-    title       text NOT NULL,
-    body_md     text NOT NULL DEFAULT '',
-    body_html   text NOT NULL DEFAULT '',
-    published   boolean NOT NULL DEFAULT true,
-    created_at  timestamptz NOT NULL DEFAULT now(),
-    updated_at  timestamptz NOT NULL DEFAULT now(),
-    UNIQUE (page_id, slug)
-);
-CREATE INDEX posts_page_created ON posts (page_id, created_at DESC);
-
-CREATE TABLE images (
-    id            uuid PRIMARY KEY,
-    blog_id       bigint NOT NULL REFERENCES blogs(id) ON DELETE CASCADE,
-    filename      text NOT NULL,
-    content_type  text NOT NULL,
-    size          integer NOT NULL,
-    data          bytea NOT NULL,
-    created_at    timestamptz NOT NULL DEFAULT now()
-);
-CREATE INDEX images_blog ON images (blog_id, created_at DESC);
-
 -- +goose Down
-DROP TABLE images;
-DROP TABLE posts;
-DROP TABLE pages;
 DROP TABLE blogs;
 DROP TABLE users;
diff --git a/internal/db/migrations/control/00002_sections.sql b/internal/db/migrations/control/00002_sections.sql
deleted file mode 100644
index 388cb17..0000000
--- a/internal/db/migrations/control/00002_sections.sql
+++ /dev/null
@@ -1,19 +0,0 @@
--- +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;
diff --git a/internal/db/migrations/control/00003_layout.sql b/internal/db/migrations/control/00003_layout.sql
deleted file mode 100644
index e8fff23..0000000
--- a/internal/db/migrations/control/00003_layout.sql
+++ /dev/null
@@ -1,56 +0,0 @@
--- +goose Up
--- Layout modules: what each area of a blog (header, columns, footer) shows.
-CREATE TABLE modules (
-    id          bigserial PRIMARY KEY,
-    blog_id     bigint NOT NULL REFERENCES blogs(id) ON DELETE CASCADE,
-    area        text NOT NULL CHECK (area IN ('header', 'left', 'right', 'above', 'below', 'footer')),
-    kind        text NOT NULL CHECK (kind IN ('title', 'logo', 'menu', 'archive', 'recent', 'html', 'rss', 'text', 'sitemap')),
-    title       text NOT NULL DEFAULT '',
-    body        text NOT NULL DEFAULT '',
-    count       integer NOT NULL DEFAULT 5,
-    sort_order  integer NOT NULL DEFAULT 0,
-    created_at  timestamptz NOT NULL DEFAULT now(),
-    updated_at  timestamptz NOT NULL DEFAULT now()
-);
-CREATE INDEX modules_blog ON modules (blog_id, area, sort_order, id);
-
--- The menu: blog pages and custom links in one ordered list.
-CREATE TABLE menu_items (
-    id          bigserial PRIMARY KEY,
-    blog_id     bigint NOT NULL REFERENCES blogs(id) ON DELETE CASCADE,
-    page_id     bigint REFERENCES pages(id) ON DELETE CASCADE,
-    label       text NOT NULL DEFAULT '',
-    url         text NOT NULL DEFAULT '',
-    sort_order  integer NOT NULL DEFAULT 0,
-    CHECK (page_id IS NOT NULL OR url <> '')
-);
-CREATE UNIQUE INDEX menu_items_page ON menu_items (page_id) WHERE page_id IS NOT NULL;
-CREATE INDEX menu_items_blog ON menu_items (blog_id, sort_order, id);
-
--- Existing blogs keep the menu they had: pages marked "show in menu", in menu
--- order, with the home page only if the theme included it.
-INSERT INTO menu_items (blog_id, page_id, sort_order)
-SELECT p.blog_id, p.id, row_number() OVER (PARTITION BY p.blog_id ORDER BY p.nav_order, p.id) - 1
-FROM pages p JOIN blogs b ON b.id = p.blog_id
-WHERE p.show_in_nav AND (NOT p.is_home OR coalesce((b.theme->>'nav_show_home')::boolean, true));
-ALTER TABLE pages DROP COLUMN show_in_nav;
-
--- ...and the layout their theme described.
-INSERT INTO modules (blog_id, area, kind, sort_order)
-SELECT id, 'header', 'title', CASE WHEN theme->>'nav_position' = 'top-bar' THEN 1 ELSE 0 END
-FROM blogs WHERE coalesce((theme->>'header_show_title')::boolean, true);
-INSERT INTO modules (blog_id, area, kind, sort_order)
-SELECT id, 'header', 'menu', CASE WHEN theme->>'nav_position' = 'top-bar' THEN 0 ELSE 1 END
-FROM blogs WHERE coalesce(theme->>'nav_position', 'below-header') <> 'left-sidebar';
-INSERT INTO modules (blog_id, area, kind, sort_order)
-SELECT id, 'left', 'menu', 0 FROM blogs WHERE theme->>'nav_position' = 'left-sidebar';
-INSERT INTO modules (blog_id, area, kind, body, sort_order)
-SELECT id, 'footer', 'text', theme->>'footer_text', 0 FROM blogs WHERE coalesce(theme->>'footer_text', '') <> '';
-INSERT INTO modules (blog_id, area, kind, sort_order)
-SELECT id, 'footer', 'rss', 1 FROM blogs WHERE coalesce((theme->>'footer_show_rss')::boolean, true);
-
--- +goose Down
-ALTER TABLE pages ADD COLUMN show_in_nav boolean NOT NULL DEFAULT true;
-UPDATE pages SET show_in_nav = EXISTS (SELECT 1 FROM menu_items m WHERE m.page_id = pages.id);
-DROP TABLE menu_items;
-DROP TABLE modules;
diff --git a/internal/db/migrations/control/00004_section_placement.sql b/internal/db/migrations/control/00004_section_placement.sql
deleted file mode 100644
index c36787e..0000000
--- a/internal/db/migrations/control/00004_section_placement.sql
+++ /dev/null
@@ -1,13 +0,0 @@
--- +goose Up
--- Announcements are placed in a column (left, main, right) at its top or bottom.
-ALTER TABLE sections DROP CONSTRAINT sections_placement_check;
-UPDATE sections SET placement = CASE placement WHEN 'above' THEN 'main-top' WHEN 'below' THEN 'main-bottom' ELSE 'left-top' END;
-ALTER TABLE sections ALTER COLUMN placement SET DEFAULT 'main-top';
-ALTER TABLE sections ADD CONSTRAINT sections_placement_check
-    CHECK (placement IN ('left-top', 'left-bottom', 'main-top', 'main-bottom', 'right-top', 'right-bottom'));
-
--- +goose Down
-ALTER TABLE sections DROP CONSTRAINT sections_placement_check;
-UPDATE sections SET placement = CASE placement WHEN 'main-top' THEN 'above' WHEN 'main-bottom' THEN 'below' ELSE 'sidebar' END;
-ALTER TABLE sections ALTER COLUMN placement SET DEFAULT 'above';
-ALTER TABLE sections ADD CONSTRAINT sections_placement_check CHECK (placement IN ('above', 'below', 'sidebar'));
diff --git a/internal/db/migrations/control/00005_per_blog_databases.sql b/internal/db/migrations/control/00005_per_blog_databases.sql
deleted file mode 100644
index 92d3fa2..0000000
--- a/internal/db/migrations/control/00005_per_blog_databases.sql
+++ /dev/null
@@ -1,12 +0,0 @@
--- +goose Up
--- Each blog gets its own database; the registry remembers which one.
--- db_name stays nullable until the Go migration 00006 has moved the content.
-ALTER TABLE blogs ADD COLUMN db_name text UNIQUE;
--- "blog_" + subdomain must fit in a 63-char Postgres identifier.
-ALTER TABLE blogs DROP CONSTRAINT blogs_subdomain_check;
-ALTER TABLE blogs ADD CONSTRAINT blogs_subdomain_check CHECK (subdomain ~ '^[a-z0-9](-?[a-z0-9]){0,57}$');
-
--- +goose Down
-ALTER TABLE blogs DROP CONSTRAINT blogs_subdomain_check;
-ALTER TABLE blogs ADD CONSTRAINT blogs_subdomain_check CHECK (subdomain ~ '^[a-z0-9](-?[a-z0-9]){0,62}$');
-ALTER TABLE blogs DROP COLUMN db_name;
diff --git a/internal/db/migrations/control/00007_drop_content.sql b/internal/db/migrations/control/00007_drop_content.sql
deleted file mode 100644
index 9daa1ac..0000000
--- a/internal/db/migrations/control/00007_drop_content.sql
+++ /dev/null
@@ -1,9 +0,0 @@
--- +goose Up
--- The content now lives in the per-blog databases (see 00006 in split.go);
--- the control database keeps only users and the blog registry.
-DROP TABLE menu_items, modules, sections, images, posts, pages;
-ALTER TABLE blogs DROP COLUMN title, DROP COLUMN tagline, DROP COLUMN theme, DROP COLUMN updated_at;
-ALTER TABLE blogs ALTER COLUMN db_name SET NOT NULL;
-
--- +goose Down
--- Not reversible: the content is gone from this database. Restore from a backup instead.