Promote AgentCompany-New to the repository root and retire the old app

The legacy application - its src, tests, landing site, promo assets, docs,
release tooling, CI workflows, and root configs - leaves the tree; it stays
reachable in history. Everything under AgentCompany-New moves up unchanged:
same package name, so the production userData/database path is untouched,
and e2e/build scripts already resolved paths relative to the project. The
developer cred.txt stays gitignored at its new location. Full verify:ci
passes from the new root.

src/main/database/migrations/034-provider-auth-sessions.ts

@@ -0,0 +1,27 @@
+export const providerAuthSessionsSchema = `
+  create table if not exists provider_auth_sessions (
+    id text primary key,
+    org_id text not null references organizations(id) on delete cascade,
+    provider_id text not null references providers(id) on delete cascade,
+    provider_key text not null,
+    employee_id text not null references employees(id) on delete cascade,
+    state text not null,
+    nonce text not null,
+    code_verifier_sha256 text not null,
+    redirect_uri text not null,
+    sign_in_url text not null,
+    partition text not null,
+    created_at text not null,
+    expires_at text not null,
+    completed_at text,
+    unique(provider_id, state)
+  );
+
+  create index if not exists idx_provider_auth_sessions_org_provider
+    on provider_auth_sessions(org_id, provider_id, created_at);
+  create index if not exists idx_provider_auth_sessions_employee
+    on provider_auth_sessions(org_id, employee_id, created_at);
+
+  insert into schema_migrations(version, name, applied_at)
+  values (34, 'provider_auth_sessions', datetime('now'));
+`;