Document logging behavior and dontlog feature

Add generate-tags step with branch, sha, edge, build number, and
semver tag formats. Enable tag events for release workflows.

.woodpecker.yaml

@@ -1,17 +1,25 @@
 when:
-  - event: [push, pull_request, manual]
+  - event: [push, pull_request, manual, tag]
 
 steps:
+  - name: generate-tags
+    image: ghcr.io/abh/woodpecker-docker-tags-plugin:sha-86e52ce
+    settings:
+      tags: |
+        branch
+        sha
+        edge
+        raw -v build-${CI_PIPELINE_NUMBER}
+        semver --format {{major}}
+        semver --format {{major}}.{{minor}}
+        semver --format {{major}}.{{minor}}.{{patch}}
+
   - name: docker
     image: woodpeckerci/plugin-kaniko
     settings:
       dockerfile: Dockerfile
       registry: harbor.ntppool.org
       repo: library/static-web
-      tags:
-        - ${CI_COMMIT_SHA:0:7}
-        - ${CI_COMMIT_BRANCH}
-        - ${{ CI_COMMIT_BRANCH == 'main' && 'latest' || CI_COMMIT_BRANCH }}
       cache: true
       username:
         from_secret: harbor_library_username

README.md

@@ -19,6 +19,22 @@ To get a shell in the container run
 
 And then run `curl -H 'Host: i.perl.org' localhost` there.
 
+## Logging
+
+Access logs are sent to stdout and error logs to stderr, making them
+available to the container runtime's log collection.
+
+The Apache configuration supports a `dontlog` environment variable. When
+set on a request, that request is excluded from the access log. This is
+useful for health check endpoints that would otherwise fill the logs.
+
+To use it, add a `SetEnvIf` directive in your site configuration:
+
+    SetEnvIf Request_URI "^/ok.txt$" dontlog
+
+This allows `/ok.txt` to serve as a health check endpoint without
+generating access log entries.
+
 ## Production image
 
 The "production image" is at harbor.ntppool.org/library/static-web:latest