chore(release): @mosaicstack/mosaic 0.0.48

Publish the accumulated framework fixes that landed on main since 0.0.47:

- #669 fix(fleet): export MOSAIC_AGENT_CLASS into the agent pane so the
  per-agent persona contract injects on relaunch (the A3a env-propagation
  gap — pane inherited the tmux server env, never the systemd .env, so
  MOSAIC_AGENT_CLASS silently dropped and personas no-op'd). Ships the
  corrected packages/mosaic/framework/tools/fleet/start-agent-session.sh.
- #665 feat(fleet): provision roster from system-type profile (H3).

Version-only bump; npm-only release (kaniko image builds are excluded for
packages/mosaic/** changes). Publishing 0.0.48 lets `mosaic update` +
`mosaic fleet install` converge the running fleet off the live local hotfix
onto the durable, registry-shipped script.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

packages/mosaic/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@mosaicstack/mosaic",
-  "version": "0.0.47",
+  "version": "0.0.48",
   "repository": {
     "type": "git",
     "url": "https://git.mosaicstack.dev/mosaicstack/stack.git",