chore: align sqlite control plane architecture

- replace default Convex control-plane wording with Rust SQLite control-plane across architecture, AGENTS, Reasonix, and design docs

- retire root Convex functions source and deploy script into recycle while keeping explicit cloud/compat/sync-replica boundaries

- add control-plane migration guard/docs and keep CodeGraph refreshed after the SQLite control-plane cutover

rust/crates/control-plane/migrations/002-ai-runtime-store.sql

@@ -0,0 +1,48 @@
+-- 002-ai-runtime-store.sql
+-- MNote ACP/Hermes runtime session store.
+
+CREATE TABLE IF NOT EXISTS ai_runtime_runs (
+  id TEXT PRIMARY KEY,
+  user_id TEXT NOT NULL,
+  workspace_id TEXT,
+  document_id TEXT,
+  session_id TEXT NOT NULL,
+  run_id TEXT NOT NULL UNIQUE,
+  title TEXT,
+  profile TEXT NOT NULL,
+  acp_runtime TEXT NOT NULL,
+  trace_id TEXT,
+  status TEXT NOT NULL,
+  runtime_json TEXT NOT NULL DEFAULT '{}',
+  payload_json TEXT NOT NULL DEFAULT '{}',
+  deleted_at TEXT,
+  created_at TEXT NOT NULL,
+  updated_at TEXT NOT NULL,
+  revision INTEGER NOT NULL DEFAULT 1
+);
+
+CREATE INDEX IF NOT EXISTS idx_ai_runtime_runs_user_session
+  ON ai_runtime_runs(user_id, session_id, updated_at);
+CREATE INDEX IF NOT EXISTS idx_ai_runtime_runs_workspace
+  ON ai_runtime_runs(workspace_id, updated_at);
+CREATE INDEX IF NOT EXISTS idx_ai_runtime_runs_document
+  ON ai_runtime_runs(document_id, updated_at);
+
+CREATE TABLE IF NOT EXISTS ai_runtime_events (
+  id TEXT PRIMARY KEY,
+  user_id TEXT NOT NULL,
+  workspace_id TEXT,
+  document_id TEXT,
+  session_id TEXT NOT NULL,
+  run_id TEXT NOT NULL,
+  profile TEXT NOT NULL,
+  acp_runtime TEXT NOT NULL,
+  event_type TEXT NOT NULL,
+  payload_json TEXT NOT NULL DEFAULT '{}',
+  created_at TEXT NOT NULL
+);
+
+CREATE INDEX IF NOT EXISTS idx_ai_runtime_events_run
+  ON ai_runtime_events(user_id, run_id, created_at);
+CREATE INDEX IF NOT EXISTS idx_ai_runtime_events_session
+  ON ai_runtime_events(user_id, session_id, created_at);