chore: remove obsolete Supabase references

.gitignore

@@ -66,7 +66,6 @@ ml/intent/data/training_data_expanded.csv
 ml/intent/venv/
 ml/intent/__pycache__/
 docs/_site/
-supabase/.temp/
 
 # Training sandbox
 training-sandbox/

_roadmap.md

@@ -37,5 +37,5 @@ engineering portfolio.
 - [x] Validate the complete research, edit, deterministic verification, and review workflow with a local Ollama model.
 - [x] Propagate cancellation through agent-run command process trees and report local-model telemetry without false precision.
 - [x] Remove the disconnected legacy `monitor` and imperative `release` command implementations while preserving public-surface compatibility tests.
-- [ ] Retire or isolate the legacy Live, training, Supabase, and experimental command surfaces with compatibility tests.
+- [ ] Isolate Live as an optional local observability protocol and retire unused training and experimental command surfaces.
 - [ ] Raise coverage in legacy workflow packages without presenting the public fixture as repository-wide coverage.

scripts/test-public-contract.sh

@@ -37,6 +37,12 @@ assert_contains Makefile "verify:"
 assert_contains .github/workflows/ci.yml "make verify"
 assert_contains .github/workflows/cd.yml "make verify"
 
+retired_backend="supa""base"
+if matches="$(git grep -in "$retired_backend" -- . ':!scripts/test-public-contract.sh')"; then
+  printf 'retired hosted backend references are still tracked:\n%s\n' "$matches" >&2
+  exit 1
+fi
+
 for file in LICENSE QUALITY.md SECURITY.md SUPPORT.md .github/ISSUE_TEMPLATE/bug_report.yml; do
   if [[ ! -f "$file" ]]; then
     printf 'missing public project contract: %s\n' "$file" >&2