fix version bump strategy

README.md

@@ -4,6 +4,43 @@ This repo provides reusable Gitea Actions as composite actions that can be refer
 
 ### Bump Version
 
+Creates or updates the version in `package.json`, commits it, creates a matching Git tag, and pushes both.
+
+Inputs:
+
+- `node_version`: Node.js version to use. Default: `24`
+- `release_line`: optional release line for dev builds when it cannot be derived from the branch or PR target. Format: `<major>.<minor>`
+- `gitea_token`: optional token used for checkout and push
+
+Branch and tag rules:
+
+- `main`: creates release tags from the latest commit message (`release/x.y.z`, `release/x.y`, `hotfix/x.y.z`) or falls back to a patch bump.
+- `release/<major>.<minor>`: creates the next beta tag for that release line, e.g. `v2.4.0-beta.3`.
+- all other branches: create a dev tag for the resolved release line using a UTC timestamp, e.g. `v2.4.0-dev.20260314153045`.
+
+Dev release line resolution order:
+
+- `inputs.release_line`
+- current branch if it matches `release/<major>.<minor>`
+- PR target branch if it matches `release/<major>.<minor>`
+- on `develop`, fallback to `major.minor` from `package.json`
+
+If no release line can be resolved for a dev build, the action fails intentionally.
+
+Examples:
+
+Commit message examples on `main`:
+
+- `release/2.4.0` -> `v2.4.0`
+- `release/2.4` -> `v2.4.0`
+- `hotfix/2.4.1` -> `v2.4.1`
+
+Branch examples:
+
+- `release/2.4` -> next `v2.4.0-beta.N`
+- feature branch in a PR to `release/2.4` -> `v2.4.0-dev.<UTC_TIMESTAMP>`
+- feature branch outside a PR with `release_line: 2.4` -> `v2.4.0-dev.<UTC_TIMESTAMP>`
+
 Example:
 
 ```yaml
@@ -18,6 +55,21 @@ jobs:
           gitea_token: ${{ secrets.GITEA_TOKEN }}
 ```
 
+Feature branch outside a PR:
+
+```yaml
+jobs:
+  bump-version:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+    steps:
+      - uses: tanztee/ci-cd/.github/actions/bump-version@main
+        with:
+          gitea_token: ${{ secrets.GITEA_TOKEN }}
+          release_line: 2.4
+```
+
 ### Build and Push Docker Image
 
 Example: