docs: the dsh route config as a displayModel source

- api-reference: the `config` source in the displayModel table, read again at
  every pane start, attach and relaunch rather than restored.
- cli-registry: `modelDetect.configResolver` (a named, read-only, bounded
  reader), the stock `deepseek-route` reader and its rules, and why the dsh
  footer pattern needs a digit.
- deepseek-integration §4: Codeman reads the route for display only, the way
  dsh-TUI resolves it; the catalog check it cannot see.
- architecture-invariants (tile grid), tile-grid-plan "as built" (owner
  feedback 1), the wiki's model row, CLAUDE.md's source order.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

docs/deepseek-integration.md

@@ -201,6 +201,18 @@ not try to set one. Configure it where the harness does: `~/.dsh/settings.yaml`
 plus a home-level `~/.dsh/cordis.patch.yml`, or a `--patch` overlay on the
 profile. That is also how you point dsh at a local or third-party provider.
 
+Codeman does READ the route, for display only: a session header names the model
+the TUI's status line draws, and while it draws none (the status bar's model
+field switched off, or not painted yet) the model the session's route config
+pins (`src/deepseek-route-config.ts`). That is dsh-TUI's own rule: the last of
+`profiles/<profile>/cordis.patch.yml` and `$DSH_HOME/cordis.patch.yml` carrying
+`config` for the `dsh-tui` row, and only when it names BOTH `provider` and
+`model`; a half-pinned route is dropped whole by the TUI and shows nothing here.
+`settings.yaml`'s `agent-default-model` is the headless default and is not read.
+The reader never writes, follows no symlink out of the dsh home, and returns the
+model id alone. The TUI can still reject a pinned route against its provider's
+model catalog at startup; the status line, when on, then shows what it chose.
+
 **Environment.** `DSH_*` and `DEEPSEEK_*` are allowlisted for `envOverrides`
 (so `DSH_HOME`, `DSH_PERMISSION_MODE`, `DEEPSEEK_API_KEY`, `DEEPSEEK_BASE_URL`
 all flow through). Provider keys with *other* names are deliberately not: a dsh