Update reference docs: fix event names, add demos, document sx-boost target

- Remove sx:afterSettle (not dispatched), rename sx:sendError → sx:requestError
- Add sx:clientRoute event (Phase 3 client-side routing)
- Add working demos for all 10 events (afterRequest, afterSwap, requestError,
  clientRoute, sseOpen, sseMessage, sseError were missing demos)
- Update sx-boost docs: configurable target selector, client routing behavior
- Remove app-specific nav logic from orchestration.sx, use sx:clientRoute event
- Pass page content deps to sx_response for component loading after server fallback

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

shared/sx/ref/bootstrap_js.py

@@ -2632,7 +2632,7 @@ PLATFORM_ORCHESTRATION_JS = """
       }
       return sxRenderWithEnv(source, merged);
     } catch (e) {
-      console.error("[sx-ref] sx:route eval error for:", source, e);
+      logInfo("sx:route eval miss: " + (e && e.message ? e.message : e));
       return NIL;
     }
   }