Fix aw-auto-update: unblock Go/GitHub network access, improve no-op prompting (#19624)

* Initial plan

* Fix aw-auto-update: add network access for Go/GitHub and improve prompting

- Add `go` and `github` ecosystems to network.allowed to unblock
  Go module proxy and GitHub release asset downloads (root cause of
  engine crash - 618 blocked firewall requests)
- Improve prompt: explicit no-op fast exit, forbid manual dependency
  resolution, fail-fast on upgrade/compile errors
- Recompile lock file with gh-aw v0.68.3

Agent-Logs-Url: https://github.com/dotnet/fsharp/sessions/5e1f098d-93ec-405f-af40-876e201dd8b2

Co-authored-by: T-Gro <46543583+T-Gro@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: T-Gro <46543583+T-Gro@users.noreply.github.com>

Author: Copilot

.github/aw/actions-lock.json

@@ -5,10 +5,10 @@
       "version": "v8",
       "sha": "ed597411d8f924073f98dfc5c65a23a2325f34cd"
     },
-    "github/gh-aw-actions/setup@v0.67.4": {
+    "github/gh-aw-actions/setup@v0.68.3": {
       "repo": "github/gh-aw-actions/setup",
-      "version": "v0.67.4",
-      "sha": "9d6ae06250fc0ec536a0e5f35de313b35bad7246"
+      "version": "v0.68.3",
+      "sha": "ba90f2186d7ad780ec640f364005fa24e797b360"
     },
     "github/gh-aw/actions/setup@v0.67.2": {
       "repo": "github/gh-aw/actions/setup",