Update dependency ubuntu to v26

.github/workflows/ci.yml

@@ -30,7 +30,7 @@ defaults:
 
 jobs:
   gate:
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 30
     permissions:
       contents: read

.github/workflows/measure-clock-chain-keep.yml

@@ -32,7 +32,7 @@ defaults:
 
 jobs:
   keepalive:
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 5
     permissions:
       actions: write

.github/workflows/measure-clock-chain.yml

@@ -43,7 +43,7 @@ defaults:
 
 jobs:
   measure-chain:
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     # At most 3 dispatch tries 15 s apart, then a sleep under 5 minutes.
     timeout-minutes: 15
     permissions:

.github/workflows/measure-clock-schedule.yml

@@ -31,7 +31,7 @@ defaults:
 
 jobs:
   tick:
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 5
     permissions:
       contents: read

.github/workflows/measure-feeds.yml

@@ -52,7 +52,7 @@ defaults:
 
 jobs:
   measure-chain:
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     # At most 3 dispatch tries 15 s apart.
     timeout-minutes: 5
     permissions:
@@ -128,7 +128,7 @@ jobs:
           echo "successor=started tries=$tries" >> "$GITHUB_STEP_SUMMARY"
 
   poll:
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     # 34 polls 10 minutes apart: the last starts 330 minutes in and takes about
     # a minute; then the upload.
     timeout-minutes: 350

.github/workflows/measure-kafka.yml

@@ -28,7 +28,7 @@ defaults:
 
 jobs:
   measure:
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 40
     permissions:
       contents: read

.github/workflows/measure-push.yml

@@ -68,7 +68,7 @@ jobs:
     # tag, so only main's code may: a dispatch on another branch is skipped
     # whole, and push-summary.mjs --run refuses a run off main as well.
     if: github.ref == 'refs/heads/main'
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     # The pushes stop starting new layer attempts after 21 minutes of their
     # step (BUDGET), so the reads, the artifact and the verdict always fit.
     timeout-minutes: 40

.github/workflows/measure-range-load.yml

@@ -53,7 +53,7 @@ jobs:
   measure:
     # A measurement is evidence of main's code only.
     if: github.ref == 'refs/heads/main'
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 45
     permissions:
       contents: read

.github/workflows/measure-thc-day.yml

@@ -46,7 +46,7 @@ defaults:
 
 jobs:
   plan:
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 10
     permissions:
       contents: read
@@ -91,7 +91,7 @@ jobs:
 
   measure:
     needs: plan
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 120
     permissions:
       contents: read
@@ -148,7 +148,7 @@ jobs:
 
   merge:
     needs: [plan, measure]
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 60
     permissions:
       contents: read

.github/workflows/measure-thc-monthly.yml

@@ -50,7 +50,7 @@ defaults:
 
 jobs:
   measure:
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 360
     permissions:
       contents: read

.github/workflows/measure-tiles.yml

@@ -68,7 +68,7 @@ jobs:
     # successor, so it leaves the group at once and its artifacts never join
     # the evidence.
     if: github.ref == 'refs/heads/main'
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     # At most 3 dispatch tries 15 s apart.
     timeout-minutes: 5
     permissions:
@@ -145,7 +145,7 @@ jobs:
 
   rounds:
     if: github.ref == 'refs/heads/main'
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     # 12 rounds 30 minutes apart: the last starts 330 minutes in and ends
     # within its 10-minute deadline; then the upload.
     timeout-minutes: 350
@@ -183,7 +183,7 @@ jobs:
 
   overlap:
     if: github.ref == 'refs/heads/main'
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     # The overlap waits at most 120 minutes for THC's day; its reads, the
     # Geomys window and the 10-minute rates take about 20 minutes more.
     timeout-minutes: 240

.github/workflows/ref-refresh.yml

@@ -48,7 +48,7 @@ jobs:
   ref:
     # The job pushes with main's code only: a dispatch on another branch is skipped whole.
     if: github.ref == 'refs/heads/main'
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 45
     permissions:
       contents: read