feat(FN-3898): add checkout/schema self-heal and import compatibility updates

- Add self-healing for legacy tasks schema/columns and checkout-lease recovery with regression coverage
- Extend companies.sh import parsing and dashboard import routes for repo subpath handling
- Fix verification command spawning to disable Corepack download prompts in engine tooling
- Update dependency-graph plugin packaging/exports and wire CLI dashboard interop types
- Add and include follow-up changesets for FN-3856, FN-3883, FN-3896, and FN-3898

Fusion-Task-Id: FN-3898

.changeset/FN-3898-checkout-columns-self-heal-followup.md

@@ -0,0 +1,5 @@
+---
+"@runfusion/fusion": patch
+---
+
+Wire the checkout-lease column self-heal as an unconditional startup compatibility backfill (`ensureTasksSchemaCompatibility`) so legacy or mesh-synced task databases no longer fail with `no such column: checkoutNodeId` when schemaVersion is already past migration 20.

packages/core/src/__tests__/db.test.ts

@@ -1191,6 +1191,52 @@ describe("schema migrations", () => {
     db.close();
   });
 
+  it("backfills missing checkout lease columns when schemaVersion is already current", () => {
+    tmpDir = makeTmpDir();
+    const fusionDir = join(tmpDir, ".fusion");
+    const legacyDb = new Database(fusionDir);
+
+    legacyDb.exec(`
+      CREATE TABLE IF NOT EXISTS __meta (key TEXT PRIMARY KEY, value TEXT);
+      CREATE TABLE IF NOT EXISTS config (
+        id INTEGER PRIMARY KEY CHECK (id = 1),
+        nextId INTEGER DEFAULT 1,
+        nextWorkflowStepId INTEGER DEFAULT 1,
+        settings TEXT DEFAULT '{}',
+        workflowSteps TEXT DEFAULT '[]',
+        updatedAt TEXT
+      );
+      CREATE TABLE IF NOT EXISTS tasks (
+        id TEXT PRIMARY KEY,
+        description TEXT NOT NULL,
+        "column" TEXT NOT NULL,
+        createdAt TEXT NOT NULL,
+        updatedAt TEXT NOT NULL
+      );
+    `);
+    legacyDb.exec("INSERT INTO __meta (key, value) VALUES ('schemaVersion', '70')");
+    legacyDb.exec("INSERT INTO __meta (key, value) VALUES ('lastModified', '1000')");
+    legacyDb.exec(`INSERT INTO tasks (id, description, "column", createdAt, updatedAt) VALUES ('FN-lease', 'legacy', 'triage', '2026-01-01', '2026-01-01')`);
+    legacyDb.close();
+
+    const db = new Database(fusionDir);
+    db.init();
+
+    const columns = db.prepare("PRAGMA table_info(tasks)").all() as Array<{ name: string }>;
+    const columnNames = columns.map((column) => column.name);
+    expect(columnNames).toContain("checkedOutBy");
+    expect(columnNames).toContain("checkedOutAt");
+    expect(columnNames).toContain("checkoutNodeId");
+    expect(columnNames).toContain("checkoutRunId");
+    expect(columnNames).toContain("checkoutLeaseRenewedAt");
+    expect(columnNames).toContain("checkoutLeaseEpoch");
+
+    const task = db.prepare("SELECT checkoutLeaseEpoch FROM tasks WHERE id = 'FN-lease'").get() as { checkoutLeaseEpoch: number | null };
+    expect(task.checkoutLeaseEpoch).toBe(0);
+
+    db.close();
+  });
+
   it("backfills legacy routines table missing agentId with safe defaults", () => {
     tmpDir = makeTmpDir();
     const fusionDir = join(tmpDir, ".fusion");

packages/core/src/db.ts

@@ -1064,6 +1064,7 @@ export class Database {
     this.migrate();
 
     // Compatibility backfills that must run even when schemaVersion is current.
+    this.ensureTasksSchemaCompatibility();
     this.ensureRoutinesSchemaCompatibility();
     this.ensureInsightRunsSchemaCompatibility();
     this.ensureEvalTaskResultsSchemaCompatibility();
@@ -1086,6 +1087,29 @@ export class Database {
    * Column additions use `hasColumn()` so they are idempotent — safe to
    * re-run even if a previous migration partially applied.
    */
+  /**
+   * Applies idempotent compatibility fixes for legacy tasks checkout lease columns.
+   *
+   * FN-3879 documented a self-heal for missing checkout lease columns, but the
+   * original column adds lived only in the `version < 20` migration block. Some
+   * legacy/mesh-synced databases report `schemaVersion >= 20` despite never
+   * receiving those columns, so task listing queries can fail with `no such
+   * column: checkoutNodeId`. Running this unconditionally on init guarantees the
+   * canonical lease columns exist.
+   */
+  private ensureTasksSchemaCompatibility(): void {
+    if (!this.hasTable("tasks")) {
+      return;
+    }
+
+    this.addColumnIfMissing("tasks", "checkedOutBy", "TEXT");
+    this.addColumnIfMissing("tasks", "checkedOutAt", "TEXT");
+    this.addColumnIfMissing("tasks", "checkoutNodeId", "TEXT");
+    this.addColumnIfMissing("tasks", "checkoutRunId", "TEXT");
+    this.addColumnIfMissing("tasks", "checkoutLeaseRenewedAt", "TEXT");
+    this.addColumnIfMissing("tasks", "checkoutLeaseEpoch", "INTEGER DEFAULT 0");
+  }
+
   /**
    * Applies idempotent compatibility fixes for legacy routines table shapes.
    *