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

.gitea/workflows/acceptance.yml

@@ -17,10 +17,10 @@ on:
     types: [opened, synchronize, reopened]
   workflow_dispatch:
 
-concurrency:
-  group: qemu                     # every workflow shares this one group: one run at a time,
-                                  # a runner-image rebuild included (Captain Bob, 2026-11-07)
-  cancel-in-progress: false
+# No concurrency group (Captain Bob, 2026-11-11, #140: "It should be global"). The one runner
+# (starshipos-vps) has capacity 1, so every job of every workflow waits its turn in Gitea's queue
+# and none is cancelled; a runner-image rebuild still blocks the rest (2026-11-07). A shared
+# concurrency group kept only one waiting run, and each run that joined cancelled it.
 
 jobs:
   acceptance:

.gitea/workflows/build.yml

@@ -13,9 +13,10 @@ on:
                                      # the server the wikis share (Captain Bob, 2026-11-07)
   workflow_dispatch:
 
-concurrency:
-  group: qemu                     # every workflow shares this one group (Captain Bob, 2026-11-07: a
-  cancel-in-progress: false       # runner-image rebuild blocks other jobs, always): one run at a time
+# No concurrency group (Captain Bob, 2026-11-11, #140: "It should be global"). The one runner
+# (starshipos-vps) has capacity 1, so every job of every workflow waits its turn in Gitea's queue
+# and none is cancelled; a runner-image rebuild still blocks the rest (2026-11-07). A shared
+# concurrency group kept only one waiting run, and each run that joined cancelled it.
 
 jobs:
   image:

.gitea/workflows/nightly-docs.yml

@@ -14,9 +14,10 @@ on:
     - cron: '0 4 * * *'        # 04:00 UTC, after the images (nightly.yml, 03:00)
   workflow_dispatch:
 
-concurrency:
-  group: qemu                     # every workflow shares this one group (Captain Bob, 2026-11-07: a
-  cancel-in-progress: false       # runner-image rebuild blocks other jobs, always): one run at a time
+# No concurrency group (Captain Bob, 2026-11-11, #140: "It should be global"). The one runner
+# (starshipos-vps) has capacity 1, so every job of every workflow waits its turn in Gitea's queue
+# and none is cancelled; a runner-image rebuild still blocks the rest (2026-11-07). A shared
+# concurrency group kept only one waiting run, and each run that joined cancelled it.
 
 jobs:
   docs:

.gitea/workflows/nightly.yml

@@ -20,10 +20,10 @@ on:
     - cron: '0 3 * * *'        # 03:00 UTC; the documents are at 04:00 (nightly-docs.yml)
   workflow_dispatch:
 
-concurrency:
-  group: qemu                     # every workflow shares this one group: one run at a time,
-                                  # a runner-image rebuild included (Captain Bob, 2026-11-07)
-  cancel-in-progress: false
+# No concurrency group (Captain Bob, 2026-11-11, #140: "It should be global"). The one runner
+# (starshipos-vps) has capacity 1, so every job of every workflow waits its turn in Gitea's queue
+# and none is cancelled; a runner-image rebuild still blocks the rest (2026-11-07). A shared
+# concurrency group kept only one waiting run, and each run that joined cancelled it.
 
 jobs:
   nightly:

.gitea/workflows/release.yml

@@ -18,10 +18,10 @@ on:
   push:
     tags: ['v*']
 
-concurrency:
-  group: qemu                     # every workflow shares this one group: one run at a time,
-                                  # a runner-image rebuild included (Captain Bob, 2026-11-07)
-  cancel-in-progress: false
+# No concurrency group (Captain Bob, 2026-11-11, #140: "It should be global"). The one runner
+# (starshipos-vps) has capacity 1, so every job of every workflow waits its turn in Gitea's queue
+# and none is cancelled; a runner-image rebuild still blocks the rest (2026-11-07). A shared
+# concurrency group kept only one waiting run, and each run that joined cancelled it.
 
 jobs:
   release:

.gitea/workflows/runner-image.yml

@@ -17,9 +17,10 @@ on:
     paths: ['ci/runner-image/**', 'Makefile']
   workflow_dispatch:
 
-concurrency:
-  group: qemu                     # every workflow shares this one group (Captain Bob, 2026-11-07: a
-  cancel-in-progress: false       # runner-image rebuild blocks other jobs, always): one run at a time
+# No concurrency group (Captain Bob, 2026-11-11, #140: "It should be global"). The one runner
+# (starshipos-vps) has capacity 1, so every job of every workflow waits its turn in Gitea's queue
+# and none is cancelled; a runner-image rebuild still blocks the rest (2026-11-07). A shared
+# concurrency group kept only one waiting run, and each run that joined cancelled it.
 
 jobs:
   image: