feat(backend): migrations Postgres testées (users, devices, resources, operations, ocr_jobs) + migrate au boot

- golang-migrate embarqué via embed (db/migrations/*.sql), MigrateDatabase(url) au boot
- ids TEXT 32-hex avec CHECK ~ '^[0-9a-f]{32}$' ; operations idempotentes UNIQUE(device_id, operation_id)
- harness db/migrations_test.go (up → assertions schéma → down, skip si PG indisponible)
- DB dev fraîche vaultdrop_dev (la DB vaultdrop héberge un prototype V2 abandonné)

backend/db/migrations/000001_create_users.down.sql

@@ -0,0 +1,3 @@
+DROP INDEX IF EXISTS idx_users_parent;
+DROP INDEX IF EXISTS idx_users_email;
+DROP TABLE IF EXISTS users;

backend/db/migrations/000001_create_users.up.sql

@@ -0,0 +1,13 @@
+CREATE TABLE users (
+    id TEXT PRIMARY KEY CHECK (id ~ '^[0-9a-f]{32}$'),
+    email VARCHAR(255),
+    display_name VARCHAR(255),
+    parent_user_id TEXT REFERENCES users(id) ON DELETE SET NULL,
+    storage_quota_bytes BIGINT DEFAULT 10737418240,
+    created_at TIMESTAMPTZ DEFAULT NOW(),
+    updated_at TIMESTAMPTZ DEFAULT NOW(),
+    deleted_at TIMESTAMPTZ
+);
+
+CREATE UNIQUE INDEX idx_users_email ON users(email) WHERE email IS NOT NULL AND deleted_at IS NULL;
+CREATE INDEX idx_users_parent ON users(parent_user_id) WHERE deleted_at IS NULL;

backend/db/migrations/000002_create_devices.down.sql

@@ -0,0 +1,2 @@
+DROP INDEX IF EXISTS idx_devices_user;
+DROP TABLE IF EXISTS devices;

backend/db/migrations/000002_create_devices.up.sql

@@ -0,0 +1,9 @@
+CREATE TABLE devices (
+    device_id TEXT PRIMARY KEY CHECK (device_id ~ '^[0-9a-f]{32}$'),
+    user_id TEXT REFERENCES users(id) ON DELETE SET NULL,
+    created_at TIMESTAMPTZ DEFAULT NOW(),
+    registered_at TIMESTAMPTZ DEFAULT NOW(),
+    last_seen_at TIMESTAMPTZ
+);
+
+CREATE INDEX idx_devices_user ON devices(user_id) WHERE user_id IS NOT NULL;

backend/db/migrations/000003_create_resources.down.sql

@@ -0,0 +1,4 @@
+DROP INDEX IF EXISTS idx_resources_category;
+DROP INDEX IF EXISTS idx_resources_parent;
+DROP INDEX IF EXISTS idx_resources_owner;
+DROP TABLE IF EXISTS resources;

backend/db/migrations/000003_create_resources.up.sql

@@ -0,0 +1,21 @@
+CREATE TABLE resources (
+    resource_id TEXT PRIMARY KEY CHECK (resource_id ~ '^[0-9a-f]{32}$'),
+    type TEXT NOT NULL CHECK (type IN ('file', 'folder')),
+    name TEXT NOT NULL,
+    parent_id TEXT REFERENCES resources(resource_id) ON DELETE CASCADE,
+    owner_id TEXT NOT NULL REFERENCES devices(device_id) ON DELETE CASCADE,
+    content_hash VARCHAR(128),
+    size_bytes BIGINT DEFAULT 0,
+    mime_type VARCHAR(255),
+    extension VARCHAR(64),
+    category VARCHAR(50) CHECK (category IN ('photo', 'video', 'document', 'audio', 'other')),
+    taken_at TIMESTAMPTZ,
+    created_at TIMESTAMPTZ DEFAULT NOW(),
+    updated_at TIMESTAMPTZ DEFAULT NOW(),
+    deleted_at TIMESTAMPTZ,
+    CONSTRAINT resources_unique_name_per_parent UNIQUE (parent_id, name)
+);
+
+CREATE INDEX idx_resources_owner ON resources(owner_id) WHERE deleted_at IS NULL;
+CREATE INDEX idx_resources_parent ON resources(parent_id);
+CREATE INDEX idx_resources_category ON resources(category) WHERE deleted_at IS NULL;

backend/db/migrations/000004_create_operations.down.sql

@@ -0,0 +1,2 @@
+DROP INDEX IF EXISTS idx_operations_device_created;
+DROP TABLE IF EXISTS operations;

backend/db/migrations/000004_create_operations.up.sql

@@ -0,0 +1,14 @@
+CREATE TABLE operations (
+    id BIGSERIAL PRIMARY KEY,
+    device_id TEXT NOT NULL REFERENCES devices(device_id) ON DELETE CASCADE,
+    operation_id TEXT NOT NULL CHECK (operation_id ~ '^[0-9a-f]{32}$'),
+    op_type TEXT NOT NULL,
+    payload JSONB NOT NULL,
+    status TEXT NOT NULL DEFAULT 'applied' CHECK (status IN ('applied', 'failed')),
+    error_code TEXT,
+    applied_at TIMESTAMPTZ DEFAULT NOW(),
+    created_at TIMESTAMPTZ DEFAULT NOW(),
+    CONSTRAINT operations_unique_per_device UNIQUE (device_id, operation_id)
+);
+
+CREATE INDEX idx_operations_device_created ON operations(device_id, created_at);

backend/db/migrations/000005_create_ocr_jobs.down.sql

@@ -0,0 +1,3 @@
+DROP INDEX IF EXISTS idx_ocr_jobs_file;
+DROP INDEX IF EXISTS idx_ocr_jobs_status;
+DROP TABLE IF EXISTS ocr_jobs;

backend/db/migrations/000005_create_ocr_jobs.up.sql

@@ -0,0 +1,15 @@
+CREATE TABLE ocr_jobs (
+    job_id TEXT PRIMARY KEY CHECK (job_id ~ '^[0-9a-f]{32}$'),
+    file_id TEXT NOT NULL REFERENCES resources(resource_id) ON DELETE CASCADE,
+    device_id TEXT NOT NULL REFERENCES devices(device_id) ON DELETE CASCADE,
+    status TEXT NOT NULL DEFAULT 'queued' CHECK (status IN ('queued', 'processing', 'done', 'failed')),
+    language VARCHAR(64) DEFAULT 'fra+eng',
+    text TEXT,
+    error TEXT,
+    created_at TIMESTAMPTZ DEFAULT NOW(),
+    started_at TIMESTAMPTZ,
+    completed_at TIMESTAMPTZ
+);
+
+CREATE INDEX idx_ocr_jobs_status ON ocr_jobs(status);
+CREATE INDEX idx_ocr_jobs_file ON ocr_jobs(file_id);