Agent profiles (AGENTS.md): per-org library, free builtins, versioning, marketplace, persona

Reusable agent definitions authored as AGENTS.md (YAML frontmatter + a Markdown body that becomes
the agent's operating guide). Mirrors the skill library, including its review hardening.

- AgentProfile entity (OrgBoard): org-scoped + versioned by (OrganizationId, ProfileKey, Version),
  NULLS NOT DISTINCT unique index; Origin Builtin|Authored|Installed; ProfileVisibility +
  ProfileStatus with the Public⟹Published invariant enforced in Apply()/SetVisibility(). AGENTS.md
  parser (YamlDotNet). AgentProfileWriter is the single upsert path (insert-only mode for install).
- Free builtins: AgentProfileSeeder seeds Aria (PO), Quill (QA), Edison (backend) on startup via a
  new IStartupSeeder + SeederRunner (runs after migrations). Idempotent, null-org, visible to all.
- Endpoints (/api/orgboard/agent-profiles): upload, list (resolvable-winner order), get versions,
  publish/unpublish, fork, marketplace (per-(key,version) AlreadyInLibrary), install (insert-only →
  clean 409, no clobber). ConfigureAgents to author/manage; ViewBoard to browse; audited.
- Persona: Agent gains Persona; ConfigureAgent stores it; AgentRunContext carries it; PromptAssembler
  injects it as "# Operating guide" (data, not instructions) so an applied profile shapes the run.
- Client: Agent profiles page (library + marketplace tabs, upload editor, publish/unlist/fork/install),
  routed + in the nav.

Verified: ArchitectureTests 8/8, IntegrationTests 55/55 (new AgentProfilesTests: builtins seeded,
upload + validation, publish, cross-org marketplace list→install→private copy, duplicate 409, per-
version flag, Member 403; persona renders as the operating guide), client build green.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/Shared/TeamUp.SharedKernel/Ai/IAgentRunContextProvider.cs

@@ -17,6 +17,7 @@ public sealed record AgentRunContext(
     IReadOnlyList<string> SkillKeys,
     IReadOnlyList<Guid> McpServerIds,
     IReadOnlyList<string> Docs,
+    string? Persona,
     Guid WorkItemId,
     string TaskTitle,
     string? TaskDescription,

src/Shared/TeamUp.SharedKernel/Startup/IStartupSeeder.cs

@@ -0,0 +1,10 @@
+namespace TeamUp.SharedKernel.Startup;
+
+/// <summary>
+/// Runs once on web-host startup, after migrations, to seed shared library content (e.g. the free
+/// builtin agent profiles). Implementations must be idempotent — startup may run repeatedly.
+/// </summary>
+public interface IStartupSeeder
+{
+    Task SeedAsync(CancellationToken cancellationToken = default);
+}