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

docs/ENVIRONMENT-FACTS.md

@@ -59,32 +59,49 @@ A wake can still be refused without any error reaching us. Read
 and a plain-English diagnosis. Refusal reasons seen in the documentation: the agent is
 paused, its budget is exhausted, its cooldown has not elapsed, or its run slot is full.
 
-## Isolated workspaces are switched off on this instance
+## Isolated workspaces: switched on 2026-11-10, and measured working
 
-The project was created asking for a git worktree per task (`executionWorkspacePolicy`
-with `workspaceStrategy.type: "git_worktree"`). **No worktree was made.** The run worked
-directly in `/tmp/pc-sandbox-2026-11-10` and committed onto `main`. The task's
-`executionWorkspaceId` and `currentExecutionWorkspace` both read `null`.
+The instance first had them off. With the flags off, the project's request for a git
+worktree per task was silently ignored: `AUD-159` worked in `/tmp/pc-sandbox-2026-11-10`
+on `main`, and the task's `executionWorkspaceId` read `null`.
 
-`GET /api/instance/settings/experimental` returns:
+Then, with the person's approval, two experimental settings were switched on:
 
 ```
-"enableIsolatedWorkspaces": false,
-"enableIsolatedWorkspacesByDefault": false,
-"enableWorktreeRunExecution": false,
+PATCH /api/instance/settings/experimental
+{"enableIsolatedWorkspaces": true, "enableWorktreeRunExecution": true}
+→ 200
 ```
 
-With `enableIsolatedWorkspaces` false, Paperclip discards a task's workspace settings
-before the run is dispatched, so the mode falls back to the shared project folder. The
-worktree code is present in the server (`git worktree add` in
-dist/services/workspace-runtime.js). Switching it on is an instance-wide experimental
-setting and a decision for the person, not a setting for one project.
+`enableIsolatedWorkspacesByDefault` was deliberately **left off**. That flag would give
+every project without a policy of its own a worktree, which would change the other nine
+projects on this instance. Only projects that ask for one now get one.
+
+The next task (`AUD-160`) made a real worktree, and Paperclip posted a "Workspace Ready"
+comment on the task naming it:
+
+```
+strategy   git_worktree
+branch     AUD-160-milestone-1-t2-read-hello-txt
+cwd        /tmp/pc-sandbox-2026-11-10/.paperclip/worktrees/AUD-160-milestone-1-t2-read-hello-txt
+baseRef    main
+deliveryState  merged_by_ancestry   (no commit was needed; the branch equals main)
+```
+
+`git worktree list` in the sandbox repository shows that path on that branch. So the
+worktree is Paperclip's job after all, once the instance allows it, and the terminal
+program never needs to run `git worktree` itself.
 
 ## Toolchain
 
-- **Go is not installed on this machine.** `go version` → not found. The terminal program
-  needs it. Under Nix, add `go` to `/etc/nixos/configuration.nix` and rebuild; do not
-  install it by hand.
+- **Go is installed** (2026-11-10), by `nix profile install nixpkgs#go` → `go1.26.5` at
+  `/home/sam/.nix-profile/bin/go`. That is the quick path: it works now, and it is not part
+  of the system closure.
+- The durable path is also prepared: `go` and `gopls` were added to
+  `environment.systemPackages` in `/etc/nixos/configuration.nix`. `nix flake check` passes
+  and the dry-run build evaluates. **The rebuild has not been run**, because `sudo` needs a
+  password here. One command finishes it: `sudo nixos-rebuild switch --flake /etc/nixos#nixos-desktop`.
+  Until then the profile copy is what runs.
 
 ## The new repository