fix(web): return every service a host row injects, and run the browser lane

The browser e2e lane had been failing wholesale since this stack moved the
agent plane into presets, and nothing caught it: 34 of 48 files. Two of the
causes are product defects, not test breakage.

`bashEnv` goes back to the host plane. `apps/cli/src/web.ts` injects it to
publish `DSH_WEB_URL`/`DSH_WEB_MODE`, so the earlier note that "nothing outside
the agent plane injects bashEnv" was simply wrong — behind a preset's `shell`
realm those variables reached no shell at all, and a `dsh web` agent could not
find the address of its own interface. This is the same criterion that returned
`subagents`: a host row that injects a service resolves before any session
exists and has no agent to key by, so the service is host-plane. `tool-bash`
consumes the host registry from inside the preset, which works because an
agent context chains to the host; only the reverse is invisible.

`tool-subagent-report` goes back with it. It is not a tool this agent calls: it
registers a continuable SETUP on the host `subagents` singleton, and that list
is not scope-aware. One copy per mounted preset meant every child was handed
`report` once per live session, so the second registration threw and a cold
subagent resume failed with `subagent-not-resumable` — a diagnostic three
layers removed from the cause.

The lane's own composition facts follow. Skill roots resolve inside a preset
now, a subtree include patches cannot reach, so the scaffold pins the roots'
documented environment fallback for its whole lifetime rather than for the boot
— presets mount per session. Without it the developer's real `~/.dsh/skills`
enters replay requests and goldens while CI sees none. The `apps/cli`
composition test pins `storage-json` for the same reason: unpinned it wrote,
and then read back, the developer's own `~/.dsh/storages/`.

Three tests now address through an agent what they used to read off the root
context, because that is where the thing lives: the tool catalog, the skill
registry, and the token meter. The seeded-history projection baseline asserts
the opposite of what it did — a detached session yields a preset-plane
projection only from a durable checkpoint written while it was live, and this
seed was written straight to persistence and never ran.

Goldens re-recorded for the hero's preset chip and the settings nav entry.

apps/web/tests/scaffold.ts

@@ -249,6 +249,31 @@ export async function launchWebScaffold(options: LaunchOptions = {}): Promise<We
   // paths at load, and an in-process boot must NEVER touch the developer's
   // real ~/.dsh document or credential file.
   const harnessHome = join(workspaceCwd, '.dsh-home')
+  // Skill discovery is model-visible input, and its roots now resolve inside a
+  // PRESET — a subtree this lane's include patches cannot reach, because the
+  // roster mounts it directly per session rather than as a row of the booted
+  // tree. The row's documented fallback is the environment, so pin that: the
+  // whole scaffold lifetime, not just the boot, since presets mount when a
+  // session is created. Without this a developer's real ~/.dsh/skills silently
+  // enters replay requests and goldens while CI sees none.
+  const skillRootEnvironment = {
+    DSH_HOME: join(workspaceCwd, '.dsh-home'),
+    DSH_AGENTS_HOME: join(workspaceCwd, '.agents-home'),
+    DSH_BUNDLED_SKILL_DIR: join(workspaceCwd, '.bundled-skills'),
+  }
+  const originalSkillRootEnvironment = Object.fromEntries(
+    Object.keys(skillRootEnvironment).map(key => [key, process.env[key]]),
+  )
+  let skillRootEnvironmentRestored = false
+  const restoreSkillRootEnvironment = (): void => {
+    if (skillRootEnvironmentRestored) return
+    skillRootEnvironmentRestored = true
+    for (const [key, value] of Object.entries(originalSkillRootEnvironment)) {
+      if (value === undefined) Reflect.deleteProperty(process.env, key)
+      else process.env[key] = value
+    }
+  }
+  Object.assign(process.env, skillRootEnvironment)
   let persistenceRoot: string
   try {
     persistenceRoot = await mkdtemp(join(tmpdir(), 'dsh-web-e2e-sessions-'))
@@ -418,6 +443,7 @@ export async function launchWebScaffold(options: LaunchOptions = {}): Promise<We
     if (process.cwd() !== originalCwd) process.chdir(originalCwd)
     const cleanupFailures = await cleanupScaffoldWorld(ctx, workspaceCwd, persistenceRoot)
     restoreCredentialEnvironment()
+    restoreSkillRootEnvironment()
     if (cleanupFailures.length > 0) {
       throw new AggregateError([error, ...cleanupFailures], 'web scaffold setup failed and cleanup was incomplete')
     }
@@ -465,6 +491,7 @@ export async function launchWebScaffold(options: LaunchOptions = {}): Promise<We
         failures.push(...await cleanupScaffoldWorld(ctx, workspaceCwd, persistenceRoot))
       } finally {
         restoreCredentialEnvironment()
+        restoreSkillRootEnvironment()
       }
       if (failures.length > 0) throw new AggregateError(failures, 'web scaffold teardown failed')
     },