feat: redesign metadata as KV store, add custom properties and WOPI Discovery

Replace one-to-one FileMetadata table with flexible ObjectMetadata KV pairs,
add custom property definitions, WOPI Discovery auto-configuration, and
per-extension action URL support.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

migrations/002_metadata_kv_redesign.sql

@@ -0,0 +1,88 @@
+-- 迁移：文件元数据系统重构
+-- 将固定列 FileMetadata 表替换为灵活的 ObjectMetadata KV 表
+-- 日期：2026-02-23
+
+BEGIN;
+
+-- ==================== 1. object 表新增 mime_type 列 ====================
+ALTER TABLE object ADD COLUMN IF NOT EXISTS mime_type VARCHAR(127);
+
+-- ==================== 2. physicalfile 表新增 checksum_sha256 列 ====================
+ALTER TABLE physicalfile ADD COLUMN IF NOT EXISTS checksum_sha256 VARCHAR(64);
+
+-- ==================== 3. 创建 objectmetadata KV 表 ====================
+CREATE TABLE IF NOT EXISTS objectmetadata (
+    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    created_at TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    object_id UUID NOT NULL REFERENCES object(id) ON DELETE CASCADE,
+    name VARCHAR(255) NOT NULL,
+    value TEXT NOT NULL,
+    is_public BOOLEAN NOT NULL DEFAULT false,
+    CONSTRAINT uq_object_metadata_object_name UNIQUE (object_id, name)
+);
+
+CREATE INDEX IF NOT EXISTS ix_object_metadata_object_id
+    ON objectmetadata (object_id);
+
+-- ==================== 4. 创建 custompropertydefinition 表 ====================
+CREATE TABLE IF NOT EXISTS custompropertydefinition (
+    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    created_at TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    owner_id UUID NOT NULL REFERENCES "user"(id) ON DELETE CASCADE,
+    name VARCHAR(100) NOT NULL,
+    type VARCHAR NOT NULL,
+    icon VARCHAR(100),
+    options JSON,
+    default_value VARCHAR(500),
+    sort_order INTEGER NOT NULL DEFAULT 0
+);
+
+CREATE INDEX IF NOT EXISTS ix_custompropertydefinition_owner_id
+    ON custompropertydefinition (owner_id);
+
+-- ==================== 5. 迁移旧数据（从 filemetadata 到 objectmetadata）====================
+-- 将 filemetadata 中的数据迁移到 objectmetadata KV 格式
+DO $$
+BEGIN
+    IF EXISTS (SELECT 1 FROM information_schema.tables WHERE table_name = 'filemetadata') THEN
+        -- 同时将 mime_type 上提到 object 表
+        UPDATE object o
+        SET mime_type = fm.mime_type
+        FROM filemetadata fm
+        WHERE fm.object_id = o.id AND fm.mime_type IS NOT NULL;
+
+        -- 将 checksum_sha256 迁移到 physicalfile 表
+        UPDATE physicalfile pf
+        SET checksum_sha256 = fm.checksum_sha256
+        FROM filemetadata fm
+        JOIN object o ON fm.object_id = o.id
+        WHERE o.physical_file_id = pf.id AND fm.checksum_sha256 IS NOT NULL;
+
+        -- 迁移 width → exif:width
+        INSERT INTO objectmetadata (id, object_id, name, value, is_public)
+        SELECT gen_random_uuid(), object_id, 'exif:width', CAST(width AS TEXT), true
+        FROM filemetadata WHERE width IS NOT NULL;
+
+        -- 迁移 height → exif:height
+        INSERT INTO objectmetadata (id, object_id, name, value, is_public)
+        SELECT gen_random_uuid(), object_id, 'exif:height', CAST(height AS TEXT), true
+        FROM filemetadata WHERE height IS NOT NULL;
+
+        -- 迁移 duration → stream:duration
+        INSERT INTO objectmetadata (id, object_id, name, value, is_public)
+        SELECT gen_random_uuid(), object_id, 'stream:duration', CAST(duration AS TEXT), true
+        FROM filemetadata WHERE duration IS NOT NULL;
+
+        -- 迁移 bitrate → stream:bitrate
+        INSERT INTO objectmetadata (id, object_id, name, value, is_public)
+        SELECT gen_random_uuid(), object_id, 'stream:bitrate', CAST(bitrate AS TEXT), true
+        FROM filemetadata WHERE bitrate IS NOT NULL;
+
+        -- 删除旧表
+        DROP TABLE filemetadata;
+    END IF;
+END $$;
+
+COMMIT;