feat(bundle): the web and one-shot apps own their own flags

dsh-web-app owns --host/--port/--dev/--workspace-root/--trusted-host and
its --help in a web-startup row; the rows it configures wait for the
webStartup service, and the client-plugin HMR receiver now ships disabled
so --dev is a row toggle rather than a runtime insert (the Loader cannot
resolve a row inserted from inside a mounting plugin).

dsh-headless owns the task positional and rejects a missing task as its own
usage error. Its runner ships disabled, not merely waiting: the schema
requires the task, and a row's config is validated when its fiber is
created, before the startup row can supply one. A composition has exactly
one command-line owner, so the patch disables the web startup row and this
one provides webStartup too, leaving the web rows on their composed
one-shot values.

The keyless web scaffold provides the same three values with no arguments,
which is what an embedding host with no command line does.

apps/web/package.json

@@ -28,6 +28,7 @@
     "@deepseek-ai/dsh-client-ui-primitives": "workspace:^",
     "@deepseek-ai/dsh-client-ui-slots": "workspace:^",
     "@deepseek-ai/dsh-client-web-react": "workspace:^",
+    "@deepseek-ai/dsh-cmdline": "workspace:^",
     "@deepseek-ai/dsh-pwsh-local": "workspace:^",
     "@types/node": "^22.0.0",
     "@types/react": "~18.3.1",

apps/web/tests/scaffold.ts

@@ -35,7 +35,6 @@ import Include, { type PatchOptions } from '@deepseek-ai/cordis-plugin-include'
 import Group from '@deepseek-ai/cordis-plugin-group'
 import { scrubRequestHeaders, stabilizeFixtureMessageIds } from '@deepseek-ai/dsh-acp-snapshot'
 import {
-  addHarnessSourceSection,
   assertEntriesLoaded,
   composeEntries,
   healProfilesModuleFallback,
@@ -65,6 +64,7 @@ import * as ToolCordis from '@deepseek-ai/dsh-tool-cordis'
 // Empty type imports carry the httpServer/agents/sessionPersistence Context merges.
 import type {} from '@deepseek-ai/dsh-host-webserver'
 import type {} from '@deepseek-ai/dsh-agent'
+import { provideCmdline } from '@deepseek-ai/dsh-cmdline'
 import { REPO_ROOT, requireDist } from './support.ts'
 
 /** Snapshot mode for the lane, from $DSH_SNAPSHOT (same vocabulary as the other snapshot suites). */
@@ -459,6 +459,16 @@ export async function launchWebScaffold(options: LaunchOptions = {}): Promise<We
     ctx.baseUrl = pathToFileURL(profileDir).href + '/'
     // This direct Loader harness supplies the same root-path capability as app-boot.
     ctx.provide('dshHomePath', dshHomePath)
+    // A host with no command line still provides one: the web bundle's startup
+    // row releases the rows waiting on it, and with no arguments each starts on
+    // the values this scaffold composed above. An exit request can only come
+    // from a rejected argument, which a fixed empty list has none of.
+    provideCmdline(ctx, {
+      args: [],
+      exit: (code) => {
+        throw new Error(`web e2e scaffold: the web app requested exit ${String(code)} with no arguments to reject`)
+      },
+    })
     await ctx.plugin(Loader)
     ctx.loader.builtins.include = Include
     // `cordis:group` beside it, exactly as `boot()` registers it: a group row is
@@ -469,9 +479,6 @@ export async function launchWebScaffold(options: LaunchOptions = {}): Promise<We
     // The shipped CLI deliberately has no dependency on this opt-in package.
     // Keep the Loader row real without broadening the product installation.
     if (options.cordisTools === true) ctx.loader.builtins['tool-cordis'] = ToolCordis
-    if (surfaceContext) {
-      ctx.inject(['systemPrompt'], (promptCtx) => { addHarnessSourceSection(promptCtx, REPO_ROOT) })
-    }
     await ctx.loader.create({
       name: 'cordis:include',
       config: { path: pathToFileURL(rootConfig).href, patches },

apps/web/tests/smoke-real.e2e.ts

@@ -485,10 +485,13 @@ describe.skipIf(!process.env.DEEPSEEK_API_KEY || notReady.length > 0)('web smoke
     child = spawn(
       process.execPath,
       [
-        '--import', tsxLoader, join(REPO_ROOT, 'apps/cli/src/bin.ts'), 'web', '--port', String(port),
+        '--import', tsxLoader, join(REPO_ROOT, 'apps/cli/src/bin.ts'), 'web',
+        // Launcher flags come first: the first token the launcher does not own
+        // starts the web app's own arguments.
         // Pin the in-browser picker: the shipped `-auto` row would resolve to
         // the native OS chooser on this bind, and no page can drive that.
         '--patch', fileURLToPath(new URL('./pin-browse-picker.overlay.yml', import.meta.url)),
+        '--port', String(port),
       ],
       {
         cwd: sessionsDir,