Crow personas and generated banter

- personas.go: backstory, prompt policy and output policy per crow;
  Hugin and Munin grounded in Grimnismal 20 and Gylfaginning 38;
  every working crow also follows a common output policy
- Personas go into each crow's instructions; Sentry keeps JSON-only
- banter.go: retrieve backstory, relationships and recent flock
  memory, then the speaking crow generates one line in character;
  max 2 per list against the list budget, never blocks work,
  unusable lines dropped
- crow.banter event, GET /api/crows, `crows personas` -> PERSONAS.md
- UI: epithets on tiles and messages, banter as quiet asides

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UQnSw4RRWp8uqpj3nsnnXF

ui/src/api.ts

@@ -75,3 +75,17 @@ export async function createNest(name: string, crows: string[]): Promise<Nest> {
   if (!res.ok) throw new Error(String(body.message ?? `Couldn't build that nest (${res.status}).`));
   return { nestId: String(body.nest_id), name: String(body.name), crows: (body.crows ?? []).map(String) };
 }
+
+// ---------- personas ----------
+export type Persona = { name: string; epithet: string; strength: string; backstory: string };
+
+export async function getCrows(): Promise<Map<string, Persona>> {
+  const out = new Map<string, Persona>();
+  try {
+    const res = await fetch("/api/crows");
+    if (res.ok) for (const p of await res.json()) out.set(String(p.name), { name: String(p.name), epithet: String(p.epithet), strength: String(p.strength), backstory: String(p.backstory) });
+  } catch {
+    // No personas: tiles show names only.
+  }
+  return out;
+}