refactor(web): remove --dev; mount the reload chain unconditionally

The client-hmr row joins the web bundle as an ordinary always-on roster
row: without a rebuild watcher rewriting client bundles it polls
unchanged files and stays idle. This deletes the --dev flag, the web
runtime's mode config, the mode-forked prompt contract, the DSH_WEB_MODE
bash variable, and the post-settlement row-creation machinery the
conditional row required. dsh web + pnpm run dev:web remains the
development loop.

apps/web/vite.config.ts

@@ -6,7 +6,7 @@ import react from '@vitejs/plugin-react'
 const src = (rel: string): string => fileURLToPath(new URL(rel, import.meta.url))
 const STANDALONE_ERROR = 'apps/web is not a standalone application: bare Vite cannot inject window.__DSH_BOOT__. '
   + 'From a repository checkout, run `pnpm dsh web`; an installed package uses `dsh web`. '
-  + 'For client-plugin HMR, run `pnpm dsh web --dev` together with `pnpm run dev:web`.'
+  + 'For client-plugin HMR, run `pnpm dsh web` together with `pnpm run dev:web`.'
 
 /** Fail before a Vite dev or preview server can expose the boot-manifest-free shell. */
 function rejectStandaloneServe(): Plugin {