Use ordered SQLite migrations (Refs #75)

src/lib/server/fleet/beta.ts

@@ -22,7 +22,6 @@ async function exclusive<T>(id: number, action: () => Promise<T>): Promise<T> {
 import { mkdir, rm, writeFile } from 'node:fs/promises';
 import { readFile, exists } from '../backends/files.js';
 import { getHostOperation } from '../hosts/index.js';
-import { ensureHostSchema } from '../hosts/schema.js';
 
 import { join, posix } from 'node:path';
 import { betaArchiveOf, configFileOf, destOfKind, type ArtifactKind } from '../config.js';
@@ -668,7 +667,6 @@ export async function reviseBeta(
                 'invalid-state'
             );
         }
-        ensureHostSchema(db());
         assertNativeActivationSettled(betaId);
         if (stagedFileChanges('beta', String(betaId)).some((row) => row.state === 'applying')) {
             throw new BetaError(
@@ -961,7 +959,6 @@ async function rollbackBetaInternal(
         versionId: br.script_version_id
     }));
 
-    ensureHostSchema(db());
     db().transaction(() => {
         const jobs = db()
             .prepare(