upgrade .github/workflows and documentation

* update all .github/workflows/ to use the latest version of
    actions and the go versions accordingly.
    (Only some github actions use a floating tag for the major version.)
  * reduce places where the go versions are hardcoded:
      * refEr to docs/Development.md from README.md
      * use `go.mod` from itest.yml.

.github/workflows/generate-markdown.yml

@@ -13,8 +13,8 @@ jobs:
   auto-update-readme:
       runs-on: ubuntu-latest
       steps:
-        - uses: actions/checkout@v2
+        - uses: actions/checkout@v5
         - name: Markdown autodocs
-          uses: dineshsonachalam/markdown-autodocs@v1.0.4
+          uses: dineshsonachalam/markdown-autodocs@v1.0.7
           with:
             output_file_paths: '[./README.md, ./docs/*.md]'

.github/workflows/go-oldstable.yml

@@ -12,10 +12,10 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Set up Go
-        uses: actions/setup-go@v4
+        uses: actions/setup-go@v5
         with:
           go-version: 'oldstable'
 

.github/workflows/go.yml

@@ -13,10 +13,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Set up Go
-        uses: actions/setup-go@v4
+        uses: actions/setup-go@v5
         with:
           go-version: "stable"
 
@@ -27,12 +27,12 @@ jobs:
         run: go vet ./...
 
       - name: gofmt
-        uses: Jerome1337/gofmt-action@v1.0.4
+        uses: Jerome1337/gofmt-action@v1.0.5
         with:
           gofmt-flags: "-l -d"
 
       - name: Revive Action
-        uses: morphy2k/revive-action@v2.7.4
+        uses: morphy2k/revive-action@v2
 
       - name: Tests
         run: go test -v ./...
@@ -46,17 +46,17 @@ jobs:
         pull-requests: write # Modver needs to write comments/status on PRs
       steps:
         - name: Checkout
-          uses: actions/checkout@v4
+          uses: actions/checkout@v6
           with:
             fetch-depth: 0 # Modver needs full history for comparison
 
         - name: Set up Go
-          uses: actions/setup-go@v4
+          uses: actions/setup-go@v5
           with:
             go-version: "stable"
 
         - name: Modver
-          uses: bobg/modver@v2.11.0
+          uses: bobg/modver@v2.12.0
           with:
             github_token: ${{ secrets.GITHUB_TOKEN }}
             pull_request_url: https://github.com/${{ github.repository }}/pull/${{ github.event.number }}

.github/workflows/itest.yml

@@ -6,9 +6,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Set up Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@v6
         with:
-          go-version: "^1.23.6"
+          go-version-file: "go.mod"
+          check-latest: true
 
       - name: Set up Node.js
         uses: actions/setup-node@v3

.github/workflows/release.yml

@@ -7,17 +7,19 @@ on:
 jobs:
   releases-matrix:
     name: Release Go binaries
+    # use oldest available ubuntu to be compatible with more libc.so revs.
     runs-on: ubuntu-22.04
     permissions:
       contents: write
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Set up Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@v6
         with:
-            go-version: '^1.23.6'
+            go-version: '^1.24.9'
+            check-latest: true
 
       - name: Build
         run: make dist