feat(config)!: one ordering for configuration sources, and a bootstrap deny rule

$DSH_HOME/.env had just become an ordinary environment layer, which left the
harness resolving user-facing values from a flattened process.env that could
no longer say where a value came from. A key stored through the web page
stayed shadowed by an older key in the user's own .env. An endpoint could be
redirected by the project: the invoking directory's .env is materialized like
every other layer, and a base URL decides where a resolved API key is sent, so
a DEEPSEEK_BASE_URL written into a model-editable workspace would send the
user's credential — and the prompts carrying their code — to whatever host
that file named.

Give every user-facing value one ordering, with four kinds of source:

  explicit for this run     per-operation override, CLI argument
  > authored by deployment  --config / --config-replace
  > this launch's shell     inherited process environment
  > product-managed store   settings.yaml, .credentials.yaml
  > discovered file         $DSH_HOME/.env
  > defaults                schema default, shipped base, public default

The domains differ only in which tiers exist. The earlier split — credentials
ranking the environment over the managed file while settings ranked over the
environment — was inconsistent: the distinguishing fact is who authored the
source, not the domain.

packages/util/environment owns an immutable snapshot with per-layer
provenance. getFrom(name, sources) searches only the layers a caller names,
and omitting one is a refusal rather than a demotion: the adapters ask for
['process', 'user-env'], so no reordering can let a project file back into a
decision it was excluded from.

isBootstrapOnly rejects, before anything is materialized, any .env setting a
variable that governs how a process launches (PATH, SHELL, NODE_OPTIONS,
LD_PRELOAD), where code or model-visible instructions load from (the whole
DSH_* namespace, HOME, XDG_*), or how the network is reached (proxy and CA
variables). The namespace is denied wholesale so a switch added later cannot
become settable by being forgotten, and there is no opt-out.

verify-config-source-ownership keeps both rules: no unregistered process.env
read under packages/*/*/src (26 allowlisted with reasons), and no apiKey,
baseURL, or headers inlined from the environment in shipped Cordis config —
removing those inlines is what makes the deployment tier meaningful.

packages/llm/llm-pi-ai/package.json

@@ -28,6 +28,7 @@
   "license": "BSD-3-Clause",
   "peerDependencies": {
     "@deepseek-ai/dsh-credentials": "^0.0.1",
+    "@deepseek-ai/dsh-environment": "^0.0.1",
     "@deepseek-ai/dsh-invariants": "^0.0.1",
     "@deepseek-ai/dsh-llm": "^0.0.1",
     "@deepseek-ai/dsh-settings": "^0.0.1",
@@ -40,6 +41,7 @@
   },
   "devDependencies": {
     "@deepseek-ai/dsh-credentials": "workspace:^",
+    "@deepseek-ai/dsh-environment": "workspace:^",
     "@deepseek-ai/dsh-invariants": "workspace:^",
     "@deepseek-ai/dsh-llm": "workspace:^",
     "@deepseek-ai/dsh-llm-deepseek": "workspace:^",

packages/llm/llm-pi-ai/src/index.ts

@@ -29,6 +29,7 @@
  */
 
 import type { Context } from 'cordis'
+import { environmentOf } from '@deepseek-ai/dsh-environment'
 import { getBuiltinProviders } from '@earendil-works/pi-ai/providers/all'
 import { LlmError } from '@deepseek-ai/dsh-llm'
 import type { AdapterRegistrationHandle } from '@deepseek-ai/dsh-llm'
@@ -99,9 +100,9 @@ export function apply(ctx: Context, config: Config): void {
     const credentials = ctx.get('credentials')
     const hit = credentials !== undefined
       ? (await credentials.resolve(ref))?.value
-      // Without the seam, read exactly the named variable so a plain
-      // cordis.yml composition works from the environment alone.
-      : process.env[ref]
+      // Without the seam the launching environment is the whole credential
+      // plane — but only that layer, never a discovered project file.
+      : environmentOf(ctx).getFrom(ref, ['process'])?.value
     if (hit !== undefined && hit.length > 0) return hit
     throw new LlmError(
       `llm-pi-ai: no credential for provider route "${provider}"; its profile resolves ${ref}, which is not`

packages/llm/llm-pi-ai/tsconfig.json

@@ -8,6 +8,9 @@
     "src"
   ],
   "references": [
+    {
+      "path": "../../util/environment"
+    },
     {
       "path": "../../../vendor/cosmokit"
     },