Add cookie banner versioning with JSONB snapshots

Introduce append-only cookie_banner_versions table with a JSONB
snapshot of consent-relevant configuration (privacy policy URL,
consent mode, expiry, categories and their cookies). Each version
has its own state (DRAFT/PUBLISHED) separate from the banner
lifecycle.

Replace the banner state enum (DRAFT/PUBLISHED/DISABLED) with a
simpler ACTIVE/INACTIVE toggle. Link consent records to the
specific published version the visitor accepted.

Signed-off-by: Émile Ré <emile@getprobo.com>

pkg/coredata/migrations/20260413T120000Z.sql

@@ -0,0 +1,47 @@
+-- Copyright (c) 2026 Probo Inc <hello@getprobo.com>.
+--
+-- Permission to use, copy, modify, and/or distribute this software for any
+-- purpose with or without fee is hereby granted, provided that the above
+-- copyright notice and this permission notice appear in all copies.
+--
+-- THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+-- REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+-- AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+-- INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+-- LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+-- OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+-- PERFORMANCE OF THIS SOFTWARE.
+
+-- Replace cookie_banner_state enum: DRAFT/PUBLISHED/DISABLED → ACTIVE/INACTIVE
+CREATE TYPE cookie_banner_state_new AS ENUM ('ACTIVE', 'INACTIVE');
+
+ALTER TABLE cookie_banners
+    ALTER COLUMN state TYPE cookie_banner_state_new
+    USING CASE
+        WHEN state::text = 'DISABLED' THEN 'INACTIVE'::cookie_banner_state_new
+        ELSE 'ACTIVE'::cookie_banner_state_new
+    END;
+
+DROP TYPE cookie_banner_state;
+ALTER TYPE cookie_banner_state_new RENAME TO cookie_banner_state;
+
+-- Version state for cookie banner configuration snapshots
+CREATE TYPE cookie_banner_version_state AS ENUM ('DRAFT', 'PUBLISHED');
+
+CREATE TABLE cookie_banner_versions (
+    id TEXT PRIMARY KEY,
+    tenant_id TEXT NOT NULL,
+    cookie_banner_id TEXT NOT NULL REFERENCES cookie_banners(id) ON DELETE CASCADE,
+    version INTEGER NOT NULL,
+    state cookie_banner_version_state NOT NULL,
+    snapshot JSONB NOT NULL,
+    created_at TIMESTAMP WITH TIME ZONE NOT NULL,
+    updated_at TIMESTAMP WITH TIME ZONE NOT NULL,
+
+    CONSTRAINT cookie_banner_versions_banner_version_key
+        UNIQUE (cookie_banner_id, version)
+);
+
+-- Add version reference to consent records
+ALTER TABLE cookie_consent_records
+    ADD COLUMN cookie_banner_version_id TEXT NOT NULL REFERENCES cookie_banner_versions(id);