refactor: read measurements from the local tree

The site compiles the index and the SQLite files from measurements/
instead of a pinned clone. The pin, the sync script, the CI clone steps,
the freshness area and its refresh handler are gone. core_probe --record
writes into measurements/ of the checkout by default, and a test fails
when a line or data file HEAD holds changed or vanished.

.github/workflows/deploy-site.yml

@@ -57,7 +57,6 @@ on:
       - "scripts/slots.py"
       - "scripts/sourceref.py"
       - "scripts/split_pack.py"
-      - "scripts/sync_measurements.py"
       - "scripts/truth.py"
       - "scripts/upstream.py"
       - "scripts/validate_schemas.py"
@@ -72,7 +71,7 @@ on:
       - "database.json"
       - "release.json"
       - "derivable.json"
-      - "measurements-pin.json"
+      - "measurements/**"
       # The Starlight project: config, components, styles, lockfile. Its
       # generated folders are gitignored and never trigger anything.
       - "website/**"
@@ -118,18 +117,6 @@ jobs:
 
       - run: npm ci --prefix website
 
-      # The core probe records live in Abdess/retrobios-measurements, read
-      # at the commit measurements-pin.json names and never at its head: a
-      # record reaches the site when the pin moves. One shallow fetch of that
-      # commit, with git alone.
-      - name: Clone the measurements at their pin
-        run: |
-          repo=$(python -c "import json; print(json.load(open('measurements-pin.json'))['repo'])")
-          commit=$(python -c "import json; print(json.load(open('measurements-pin.json'))['commit'])")
-          git init -q .cache/measurements
-          git -C .cache/measurements fetch -q --depth 1 "$repo" "$commit"
-          git -C .cache/measurements checkout -q --detach "$commit"
-
       - name: Validate data contracts
         run: python scripts/validate_schemas.py
 
@@ -149,7 +136,7 @@ jobs:
 
       - name: Generate site
         run: |
-          python scripts/generate_site.py --require-measurements
+          python scripts/generate_site.py
           python scripts/generate_readme.py --db database.json --platforms-dir platforms
           # starlight-links-validator fails the build on a dead link or anchor.
           npm run build --prefix website