refactor(apps): move forte-drop apps from base to upc-dev overlay

forte-drop, forte-drop-mcp and forte-drop-postgresql lived under apps/base/
but were only ever wired into the upc-dev overlay (never listed in
apps/base/kustomization.yaml). They carry hackathon-domain hardcoded values
and must not sync to upc-prod, so they belong in the overlay alongside
dbunk-demo — per danijel.simeunovic's review on PR #18.

- git mv the three dirs into apps/overlays/upc-dev/ (history preserved)
- rewrite overlay kustomization refs from ../../base/forte-drop* to local
- repoint forte-drop-postgresql Application path
  apps/base/... -> apps/overlays/upc-dev/forte-drop-postgresql/resources

Render-verified: kubectl kustomize apps/overlays/upc-dev differs only by the
postgres path line; apps/overlays/upc-prod render byte-identical (forte-drop
never reaches prod).

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

apps/overlays/upc-dev/forte-drop/namespace.yaml

@@ -0,0 +1,17 @@
+# Owns the forte-drop namespace shared by the web + mcp deployments and the
+# postgres StatefulSet (infra overlay). sync-wave -1 ensures the namespace exists
+# before the namespaced Secrets/PDB in this base apply (avoids a first-sync
+# "namespaces forte-drop not found" race when the business-apps parent syncs).
+# Prune=false so removing this base never cascade-deletes the namespace (and with
+# it postgres data + the mcp deployment) — matches the earlier decision to keep
+# namespace ownership decoupled from any single workload.
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: forte-drop
+  annotations:
+    argocd.argoproj.io/sync-wave: "-1"
+    argocd.argoproj.io/sync-options: Prune=false
+  labels:
+    app.kubernetes.io/managed-by: argocd
+    app.kubernetes.io/part-of: apps