Go module with the task tree screen; worktrees on and measured; Go installed

CHECKLIST.md

@@ -5,7 +5,8 @@ Tick each line. Nothing after the first unchecked line should be started early.
 ## Before you start
 
 - [x] Paperclip answers: `curl -s -H "Authorization: Bearer $PAPERCLIP_BOARD_KEY" http://127.0.0.1:3100/api/health` → 200.
-- [ ] Go is installed: `go version` → **still not installed** (checked 2026-11-10). Needed before Milestone 2.
+- [x] Go is installed: `go version` → `go1.26.5` from `~/.nix-profile` (2026-11-10). The
+      NixOS config change is staged but not rebuilt; see `docs/ENVIRONMENT-FACTS.md`.
 - [x] You are using the **user** key (`PAPERCLIP_BOARD_KEY`), not the agent key.
 
 ## Milestone 1 — one task, really run (no interface) — PASSED 2026-11-10
@@ -30,9 +31,14 @@ been measured.
 
 ## Milestone 2 — task tree and reply box
 
-- [ ] Create the Go module in `tui/`.
-- [ ] Screen 1 reads tasks for one project; blockers read **per task** (`/api/issues/{id}/diagnostics/blockers`), never from the list.
-- [ ] Screen 4 shows the thread and posts a reply with the user key.
+- [x] Create the Go module in `tui/`. → `tui/`, module `paperclip-harness/tui`, Bubble Tea +
+      Lipgloss + BubbleZone. `go build ./...` and `go vet ./...` are clean.
+- [x] Screen 1 reads tasks for one project; blockers read **per task** (`/api/issues/{id}/diagnostics/blockers`), never from the list.
+      → seen in a real terminal: `TODO (1) / BLOCKED (1) / DONE (2)`, with
+      `[AUD-161 todo]` shown against the blocked task. Resize shows "too small" below
+      56×12 instead of a broken tree.
+- [ ] Screen 4 shows the thread and posts a reply with the user key. → client call `PostComment`
+      exists; the screen does not.
 - [ ] Pass: move a blocked task forward from the terminal, no browser, no shell.
 
 ## Milestone 3 — add a task, watch it work