Add auto-tag daily version bump workflow

[ymodlin]

Summary

• Adds the auto-tag workflow to master so the scheduled cron and workflow_dispatch triggers work (GitHub only runs these from the default branch)
• The workflow itself checks out and pushes to dev — this PR just makes it discoverable by GitHub Actions

Context

• Full workflow was developed and merged to dev via PR Add auto-tag daily version bump workflow #372 and Ignore scripts/, CLAUDE.md, .gitignore in auto-tag filter #373
• Needs to exist on master for schedule/dispatch to function

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR adds the auto-tag workflow to the master branch to enable GitHub Actions scheduled cron and workflow_dispatch triggers, which only function from the default branch. The workflow itself operates on the dev branch, automatically bumping the build version number in MODULE_VERSION and creating corresponding git tags when meaningful code changes are detected.

Changes:

• Adds GitHub Actions workflow that runs daily at 14:00 UTC to automatically increment the build number (4th component) of MODULE_VERSION in kernel/realsense/d4xx.c
• Workflow includes smart filtering to skip version bumps for changes in non-code directories (.github/, test/, docs/, scripts/, etc.)
• Implements comprehensive validation and error handling with branch guards, change detection, and post-update verification

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[Copilot]

The version parsing and increment logic has two potential robustness issues: (1) The IFS read assumes exactly 4 dot-separated components but doesn't validate this - if MODULE_VERSION has fewer or more components, variables could be empty or truncated silently. (2) The arithmetic expansion $((build + 1)) will fail if the build component is non-numeric. Consider adding validation: if [[ -z "$major" || -z "$minor" || -z "$patch" || -z "$build" ]]; then echo "::error::Version must have exactly 4 components"; exit 1; fi and if ! [[ "$build" =~ ^[0-9]+$ ]]; then echo "::error::Build number must be numeric"; exit 1; fi

Suggested change

	IFS='.' read -r major minor patch build <<< "$current"
	IFS='.' read -r major minor patch build <<< "$current"
	if [[ -z "$major" || -z "$minor" || -z "$patch" || -z "$build" ]]; then
	echo "::error::Version must have exactly 4 components"
	exit 1
	fi
	# Ensure there are no extra components beyond major.minor.patch.build
	if [[ "$build" == *.* ]]; then
	echo "::error::Version must have exactly 4 components"
	exit 1
	fi
	if ! [[ "$build" =~ ^[0-9]+$ ]]; then
	echo "::error::Build number must be numeric"
	exit 1
	fi