merge: feat/wf5-securestorage into the 0.0.50 integration line

Brings the per-agent harness-home work (FLEET_SEAT) onto the release line.
Clean merge, no conflicts.

packages/mosaic/src/commands/fleet.ts

@@ -38,6 +38,11 @@ import {
   registerFleetAgentCrudCommands,
   type FleetAgentCrudCommandDeps,
 } from './fleet-agent-crud-command.js';
+import {
+  registerFleetAgentScaffoldCommand,
+  type FleetAgentScaffoldCommandDeps,
+} from './fleet-agent-scaffold-command.js';
+import { registerFleetAdoptCommand } from './fleet-adopt-command.js';
 import {
   registerFleetMigrationCommand,
   type FleetMigrationCommandDeps,
@@ -63,6 +68,7 @@ import { registerFleetBacklogCommand } from './fleet-backlog.js';
 import { registerFleetPersonaCommand } from './fleet-personas.js';
 import { registerFleetProfileCommand } from './fleet-profiles.js';
 import { registerFleetProvisionCommand } from './fleet-provision.js';
+import { registerFleetLaunchCommand, type FleetLaunchCommandDeps } from './fleet-launch-command.js';
 
 /**
  * A function that spawns a command with inherited stdio (TTY passthrough).
@@ -97,6 +103,10 @@ export interface FleetCommandDeps {
    */
   sleepFn?: SleepFn;
   mosaicHome?: string;
+  /** User-owned fleet/auth/config root. Defaults to ~/.mosaic. */
+  mosaicUserHome?: string;
+  /** Test/embedding seam for the final process-replacing fleet launch. */
+  fleetLauncher?: FleetLaunchCommandDeps['launcher'];
   frameworkRoot?: string;
   /**
    * Injectable TTY check for `fleet init` wizard. Defaults to process.stdin.isTTY.
@@ -104,6 +114,8 @@ export interface FleetCommandDeps {
    */
   isStdinTTY?: boolean;
   projectionApplier?: FleetAgentCrudCommandDeps['projectionApplier'];
+  /** Test-only user-data root for `fleet agent new` (production: ~/.mosaic). */
+  fleetDataHome?: FleetAgentScaffoldCommandDeps['fleetDataHome'];
   reconcileDeps?: FleetReconcilerCommandDeps['reconcileDeps'];
   migrationDeps?: Omit<FleetMigrationCommandDeps, 'mosaicHome'>;
 }
@@ -2042,6 +2054,14 @@ export function registerFleetCommand(program: Command, deps: FleetCommandDeps =
   // fleet/ directory as the roster and heartbeats.
   registerFleetBacklogCommand(cmd, () => cmd.opts<{ mosaicHome: string }>().mosaicHome);
 
+  // User-facing per-agent profile.json is the launch-composition SSOT. It is
+  // intentionally independent of roster-v2, whose lifecycle/topology registry
+  // does not model auth bundles, overlays, plugins, skills, or seat env.
+  registerFleetLaunchCommand(cmd, () => cmd.opts<{ mosaicHome: string }>().mosaicHome, {
+    ...(deps.mosaicUserHome === undefined ? {} : { userHome: deps.mosaicUserHome }),
+    ...(deps.fleetLauncher === undefined ? {} : { launcher: deps.fleetLauncher }),
+  });
+
   // System-type profiles (H2): declarative persona roster + topology, resolved
   // from <mosaicHome>/fleet/profiles/*.yaml using the same --mosaic-home flag.
   registerFleetProfileCommand(cmd, () => cmd.opts<{ mosaicHome: string }>().mosaicHome);
@@ -2055,6 +2075,18 @@ export function registerFleetCommand(program: Command, deps: FleetCommandDeps =
   // profile. DRY-RUN by default; --write persists under the same --mosaic-home.
   registerFleetProvisionCommand(cmd, () => cmd.opts<{ mosaicHome: string }>().mosaicHome);
 
+  // `fleet agent new` owns user-data harness homes under ~/.mosaic. The
+  // existing roster-v2 CRUD remains direct fleet control-plane CRUD, so there
+  // is one `agent` namespace but deliberately separate state authorities.
+  registerFleetAgentScaffoldCommand(cmd, {
+    ...(deps.fleetDataHome === undefined ? {} : { fleetDataHome: deps.fleetDataHome }),
+    mosaicHomeFor: () => cmd.opts<{ mosaicHome: string }>().mosaicHome,
+  });
+  // The counterpart to launch's refusals: launch will not delete a real directory sitting on
+  // a managed path, and this is how one gets moved out of the way instead.
+  registerFleetAdoptCommand(cmd, {
+    ...(deps.fleetDataHome === undefined ? {} : { fleetDataHome: deps.fleetDataHome }),
+  });
   // Roster-v2 desired-state mutations belong directly to the fleet control
   // plane; they do not share the root `mosaic agent` gateway-backed surface.
   registerFleetAgentCrudCommands(cmd, deps);