chore: cleanup leftover dirs from ManaCore→Mana rename + document apps/api

Removed:
- apps/manacore/ — three Svelte files were byte-identical duplicates of
  the apps/mana/ versions, leftover from the 2025 rename. Untracked .env
  files in the same dir were also cleared.
- 21 empty apps/*/apps/web-archived/ directories — leftover from the
  unification move, never tracked in git.
- services/it-landing/ — empty directory, picked up by the services/*
  workspace glob for no reason.
- apps/news/apps/server-archived/ — empty.

Fixed:
- scripts/mac-mini/status.sh: COMPOSE_PROJECT_NAME fallback was still
  manacore-monorepo from before the rename.

Documented:
- Root CLAUDE.md now describes apps/api/ (the @mana/api unified backend)
  as a top-level peer to apps/mana/. It was completely missing from the
  trimmed CLAUDE.md, which made the layout look frontend-only.

scripts/mac-mini/status.sh

@@ -78,7 +78,7 @@ if docker info >/dev/null 2>&1; then
     # every running container, and report any compose service whose
     # container_name is not currently up.
     if [ -f "$COMPOSE_FILE" ]; then
-        DEFINED=$(docker compose -p "${COMPOSE_PROJECT_NAME:-manacore-monorepo}" \
+        DEFINED=$(docker compose -p "${COMPOSE_PROJECT_NAME:-mana-monorepo}" \
             -f "$COMPOSE_FILE" config --format json 2>/dev/null \
             | python3 -c '
 import sys, json