refactor(db): port service clone/move ops to sqlc (#76)

Tranche 2: cloneServiceRow's INSERT...SELECT (volumes and traefik_labels
now read straight from the source row — traefik_labels was silently
dropped before, and the jsonb param round-trip goes away), domain and
variable copies, name-conflict counts, move UPDATE, project owner check.
Also fixes serviceWriteAccess: user_id is a context string, not a
uuid.UUID — the tranche-1 cast silently failed owner checks for
non-admins. Live tests cover the domain invariants and a full clone
round-trip (config, domains, variables).

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Co-authored-by: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

app/backend/sqlc/queries/service_ops.sql

@@ -0,0 +1,38 @@
+-- name: CountServicesByName :one
+SELECT COUNT(*) FROM services WHERE project_id = $1 AND name = $2;
+
+-- name: GetServiceEnvironment :one
+SELECT COALESCE(environment, '') FROM services WHERE id = $1;
+
+-- name: CloneServiceRow :exec
+INSERT INTO services
+    (id, project_id, name, environment_id, service_type, source_type, source_url, image_name,
+     build_command, start_command, type, status, image, command, environment,
+     git_repo, git_branch, build_path, cpu, memory, replicas, port, domain,
+     healthcheck_path, restart_policy, volumes, maintenance_mode, basic_auth_users,
+     builder, cpu_reserve, memory_reserve, static_build_cmd, static_dir,
+     traefik_labels, created_at, updated_at)
+SELECT $1, $2, $3, $4, service_type, source_type, source_url, image_name,
+     build_command, start_command, type, 'stopped', image, command, $5,
+     git_repo, git_branch, build_path, cpu, memory, replicas, port, domain,
+     healthcheck_path, restart_policy, volumes, $6, $7,
+     builder, cpu_reserve, memory_reserve, static_build_cmd, static_dir,
+     traefik_labels, $8, $8
+FROM services s WHERE s.id = $9;
+
+-- name: CloneServiceDomains :exec
+INSERT INTO service_domains (service_id, domain, is_default, cert_type)
+SELECT $1, domain, is_default, cert_type FROM service_domains sd WHERE sd.service_id = $2;
+
+-- name: CloneServiceVariables :exec
+INSERT INTO environment_variables (id, service_id, key, value, is_secret)
+SELECT gen_random_uuid(), $1, key, value, is_secret FROM environment_variables ev WHERE ev.service_id = $2;
+
+-- name: DeleteServiceByID :exec
+DELETE FROM services WHERE id = $1;
+
+-- name: MoveServiceProject :execrows
+UPDATE services SET project_id = $1, environment_id = $2, updated_at = $3 WHERE id = $4;
+
+-- name: GetProjectOwner :one
+SELECT owner_id FROM projects WHERE id = $1;