Make every identity editable: agent and operator names plus avatars

- Migration 049: avatar_emoji/avatar_color on agents and employees
- updateAgent accepts a new name (mention-name validated) and avatar;
  new updateEmployeeProfile renames the operator and sets their avatar
- Avatars are emoji-on-color tiles (renderer CSP blocks remote images);
  an AvatarDirectoryContext built from the snapshot lets the shared
  Avatar component honor custom looks at every call site - chat rows,
  conversation list, org chart, office card, sidebar - without
  threading props through pages
- Team edit dialog gains Name + avatar editor (CEO included); the
  sidebar foot opens an Edit-profile dialog for the operator
- e2e: rename an agent to a new mention handle with an emoji avatar,
  edit the operator profile, both verified in the live shell

src/shared/commands/organization.ts

@@ -27,6 +27,8 @@ export interface CreateOrganizationInput {
 export interface UpdateAgentInput {
   orgId: string;
   agentId: string;
+  /** New display name; omit to keep the current one. */
+  name?: string;
   role: string;
   title: string;
   roleLevel: string;
@@ -34,6 +36,18 @@ export interface UpdateAgentInput {
   budgetCents: number;
   modelProviderId: string | null;
   modelId: string | null;
+  /** Emoji shown on the avatar tile; empty string clears it. */
+  avatarEmoji?: string;
+  /** Background color for the avatar tile; empty string clears it. */
+  avatarColor?: string;
+}
+
+export interface UpdateEmployeeProfileInput {
+  orgId: string;
+  employeeId: string;
+  displayName: string;
+  avatarEmoji?: string;
+  avatarColor?: string;
 }
 
 export interface CreateAgentInput {