ci: one queue for all of CI, nothing cancelled (#140)

Every workflow shared the concurrency group qemu. A group keeps one running
and one waiting run, and a run that joins cancels the one waiting: Build
runs 245 and 247 were cancelled at 0 s by PR 164's Acceptance runs.

Captain Bob, 2026-11-11: "It should be global"; the runner has capacity 1.
So the concurrency block is removed from all six workflows (a comment in
each says why): with one runner at capacity 1 every job waits its turn in
Gitea's queue and none is cancelled, and a runner-image rebuild still
blocks the rest. CLAUDE.md's CI section corrected; FABRIC-3 XLVIII.19.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017RzZgrf7V7Zk2iczBXDRbm

.claude/CLAUDE.md

@@ -358,8 +358,11 @@ present in `logs/`:
 **Corrected 2026-11-10** — this file previously named stale job IDs (`build-amd64-iso`,
 `build-aarch64-iso`, `build-riscv64-img`) and said "No QEMU boot step in CI."
 
-Six workflows in `.gitea/workflows/`; all share a single `qemu` concurrency group
-(`cancel-in-progress: false`) so at most one run executes at a time:
+Six workflows in `.gitea/workflows/`. **One job at a time across all of CI, and none cancelled**
+(corrected 2026-11-11, #140 -- Captain Bob: "It should be global"): there is no concurrency group;
+the one runner (`starshipos-vps`) has capacity 1, so every job of every workflow waits its turn in
+Gitea's queue. The shared `qemu` group this file described kept only one waiting run, and each run
+that joined cancelled it:
 - **`acceptance.yml`** — PR gate into `master`: 3 QEMU boots (amd64/aarch64/riscv64)
   + PC stick loaded high + `make -C v4 test-32`, all via `scripts/nightly.sh`; branch
   protection requires this check to pass before the merge button unlocks.