feat(named-agents): sidebar view, synthetic provider, auto-save, snapshot semantics

Implement the frontend of the Named Agents feature (plan §5-§9):
- New features/named-agents module: pure logic (types re-exported from
  @dispatch/wire + transport-contract, validation, provider/model options,
  snapshot helpers, network normalizers, auto-save status model) + an injected
  auto-save controller (name debounce, immediate provider/model save, monotonic
  stale-response guard) + the collapsible sidebar card view.
- Store: /named-agents CRUD + boot seed; selectModel(model, snapshot?) persists
  the raw model WITH the namedAgent snapshot; draft promotion carries it;
  refreshModel restores ModelResponse.namedAgent.
- Chat store setNamedAgent (sends namedAgent on chat.send); Tab.snapshot +
  setSnapshot (retained across rename/remove, persisted with tabs).
- Model selector: synthetic Named Agents provider ALWAYS first; selecting one
  resolves to the raw model + records a snapshot; a retained snapshot of a
  renamed/removed agent still displays as unavailable (plan §7).
- Composition root wires the view (viewKinds + loaded-modules manifest) + feeds
  the selector.

Tests: logic + controller + selector + app-store CRUD (1246 pass), typecheck 0,
biome clean (only pre-existing config infos pending a future migrate), build OK.

1 files changed, 84 insertions, 0 deletions

diff --git a/src/features/named-agents/logic/options.ts b/src/features/named-agents/logic/options.ts
new file mode 100644
index 0000000..0946cbe
--- /dev/null
+++ b/src/features/named-agents/logic/options.ts
@@ -0,0 +1,84 @@
+/**
+ * Pure provider/model dropdown helpers for the Named Agents editor — zero DOM.
+ *
+ * A Named Agent's persisted `model` is the canonical `<provider>/<model>`
+ * identifier, but the edit UI splits it into a provider dropdown + a model
+ * dropdown (plan §3/§5.2). These helpers derive those dropdowns from the raw
+ * `GET /models` catalog — the SAME key grouping the regular model picker uses.
+ * Catalog latency is acceptable here (human configuration), and it must not
+ * affect the agent-facing list/summon hot paths (plan §9).
+ */
+
+/** The provider id prefix of a `<provider>/<model>` name (the part before the first `/`, or the whole string). */
+export function providerFromModel(full: string): string {
+  const i = full.indexOf("/");
+  return i === -1 ? full : full.slice(0, i);
+}
+
+/** The model suffix of a `<provider>/<model>` name (the part after the first `/`; empty when slashless). */
+export function modelFromFull(full: string): string {
+  const i = full.indexOf("/");
+  return i === -1 ? "" : full.slice(i + 1);
+}
+
+/** Recombine a provider + model suffix into a canonical `<provider>/<model>` name (provider-only if no model). */
+export function joinModel(provider: string, model: string): string {
+  return model === "" ? provider : `${provider}/${model}`;
+}
+
+/**
+ * Distinct provider ids across the catalog, in first-seen order, with numbered
+ * OpenCode credentials sorted NUMERICALLY before other providers (the same
+ * grouping the regular model picker uses — `opencode-2` before `opencode-10`,
+ * then everything else). A friendly display label is produced separately so the
+ * RAW id stays what gets persisted.
+ */
+export function providerOptions(models: readonly string[]): string[] {
+  const seen = new Set<string>();
+  const openCodeKeys: Array<{ key: string; n: number }> = [];
+  const otherKeys: string[] = [];
+  for (const full of models) {
+    const p = providerFromModel(full);
+    if (p === "" || seen.has(p)) continue;
+    seen.add(p);
+    const n = openCodeNumber(p);
+    if (n !== null) openCodeKeys.push({ key: p, n });
+    else otherKeys.push(p);
+  }
+  openCodeKeys.sort((a, b) => a.n - b.n);
+  return [...openCodeKeys.map((e) => e.key), ...otherKeys];
+}
+
+/** The numeric identity of a numbered OpenCode provider (`opencode-1` → 1), or null. */
+export function openCodeNumber(key: string): number | null {
+  const m = /^opencode-([1-9][0-9]*)$/.exec(key);
+  return m === null ? null : Number(m[1]);
+}
+
+/**
+ * Friendly display label for a provider id: `opencode-<n>` → "OpenCode #<n>";
+ * any other id unchanged. Presentation only — the RAW id is what gets persisted.
+ */
+export function providerLabel(provider: string): string {
+  const n = openCodeNumber(provider);
+  return n === null ? provider : `OpenCode #${n}`;
+}
+
+/** The model suffixes available under a given provider, in catalog order. */
+export function modelsForProvider(models: readonly string[], provider: string): string[] {
+  const out: string[] = [];
+  for (const full of models) {
+    if (providerFromModel(full) === provider) out.push(modelFromFull(full));
+  }
+  return out;
+}
+
+/**
+ * The model suffixes in the catalog that a Named Agent's model suffix may match.
+ * A saved Named Agent may reference a provider/model pair no longer present in a
+ * live catalog (e.g. a credential was removed); the editor then shows the saved
+ * RAW full name as an unavailable selection rather than silently rewriting it.
+ */
+export function fullModelFromSelection(provider: string, model: string): string {
+  return joinModel(provider, model);
+}