go: Phase 9 closed — 12 end-to-end programs, total 609/609 [nothing]

12 canonical Go programs running through the full pipeline (lex +
parse + types + eval + sched + stdlib): sieve-of-Eratosthenes via
boolean slice (modulo-free), linear search, slice reverse, fib(10),
sum-of-squares via generic Map+Reduce, word-freq counter, channel
pipeline (gen→sq→sum), worker pool, bubble sort, sentence-reverse,
Filter+len, Ackermann, defer+recover on div-by-zero.

Each test threads ONE self-contained Go program through go-eval-
program. The v0 limitations chiselled in earlier phases (float
division, sync spawn, type erasure, nil-as-unbound) are now
durable as commit-trail artifacts; e2e variants written to avoid
them where possible. HTTP-ish ping-pong + WaitGroup deferred
(real preemption + sync package needed).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

lib/go/scoreboard.md

@@ -1,6 +1,6 @@
 # Go-on-SX Scoreboard
 
-**Total: 597 / 597 tests passing**
+**Total: 609 / 609 tests passing**
 
 |  | Suite | Pass | Total |
 |---|---|---|---|
@@ -10,6 +10,7 @@
 | ✅ | eval | 106 | 106 |
 | ✅ | runtime | 40 | 40 |
 | ✅ | stdlib | 41 | 41 |
-| ⬜ | e2e | 0 | 0 |
+| ✅ | e2e | 12 | 12 |
+
 
 Generated by `lib/go/conformance.sh`.