sidebar: click-to-rename org/company/team + strip synthetics from world viz

Two related pieces of the "kill My Workspace" cleanup, landed
together because they share the same file:

Backend

- Three tiny inline-rename endpoints:
    PATCH /api/orgs/{id}/name
    PATCH /api/companies/{id}/name
    PATCH /api/teams/{id}/name
  Each takes { name: string }, trims + rejects empty, returns 204.
  Backed by rename_org / rename_company / rename_team in cm-db —
  single-row UPDATEs scoped to the caller's workspace, NotFound if
  the id isn't visible.
- Registered next to the existing PATCH /:id (topology) routes so
  they don't collide.

Frontend

- StructureTree accepts an optional onRename and canRename.
  TreeRow: click on the label text of a renamable node → the span
  becomes an <input>, focus + select-all, save on Enter or blur,
  cancel on Escape. The rest of the row (row chevron / row body)
  still navigates + selects as before, so single-click behaviour
  is preserved for everything except the name text itself.
  react-hooks/set-state-in-effect avoided by resetting the draft
  in the enterEdit() click handler instead of inside a useEffect.

- Dashboard passes canRename={item.level !== "claw" && !synthetic}
  (claws don't have a rename endpoint yet; synthetic scaffolding
  gets reified into real rows in the next commit — the wizard
  auto-materialize + orphan-migration dialog).
  onRename fires the corresponding PATCH and calls router.refresh()
  so the label lands in every consumer of the tree.

- World viz seed: new stripSynthetics(roots) helper walks the tree
  and lifts children of any synthetic container up to their
  grandparent's level. worldCanvasRoots feeds through this before
  narrowRoots(). Result: the Live viz no longer shows "My Workspace"
  or "Teams" nodes — real agents orbit the world root directly
  (which is what you were asking for). Sidebar tree still shows
  them so orphaned agents remain visible until the migration lands.

crates/cm-api/src/routes/orgs.rs

@@ -152,6 +152,27 @@ pub struct OrgDetail {
 }
 
 /// `GET /api/orgs/{id}` — an org's graph + node→company bindings.
+/// `PATCH /api/orgs/{id}/name` — inline rename from the sidebar. Trims the
+/// input and rejects empty; returns 204 on success, 404 if the id isn't
+/// visible in the caller's workspace.
+#[derive(Deserialize)]
+pub struct RenameOrgRequest {
+    pub name: String,
+}
+pub async fn rename_org(
+    State(state): State<AppState>,
+    Authed(user): Authed,
+    Path(id): Path<Uuid>,
+    Json(body): Json<RenameOrgRequest>,
+) -> Result<StatusCode, ApiError> {
+    let name = body.name.trim();
+    if name.is_empty() {
+        return Err(ApiError::BadRequest);
+    }
+    cm_db::repo::orgs::rename_org(&state.pool, id, user.workspace_id, name).await?;
+    Ok(StatusCode::NO_CONTENT)
+}
+
 /// `DELETE /api/orgs/{id}` — remove the org (structural: companies survive, just
 /// ungrouped from it).
 pub async fn delete_org(