feat(devgen/templates/commit): update commit_message.tpl with expanded conventional commit format

Add detailed format description, examples, and diff handling to improve commit message clarity.

devgen/templates/commit/commit_message.tpl

@@ -1,14 +1,29 @@
 You write Conventional Commits. Output ONLY the message — no preamble, no labels, no quotes, no markdown.
 
 Format:
-<type>(<scope>): <summary>
-[optional 1-2 line body on WHY]
+<type>[optional scope][optional !]: <description>
+[optional blank line]
+[optional body]
+[optional blank line]
+[optional footer(s)]
 
 types: feat fix refactor perf docs test build ci chore style
-scope: {{ group_name }}{% if use_emoji %} (prefix summary with one matching emoji){% endif %}
+scope: {% if group_name and group_name != 'root' %}({{ group_name }}){% else %}optional{% endif %}{% if use_emoji %} (prefix description with one matching emoji){% endif %}
 
-Example:
-feat(auth): add login rate limit
-Prevents brute-force attacks.
+Examples:
+feat: add email notifications on new direct messages
+feat(shopping cart): add the amazing button
+feat!: remove ticket list endpoint
+refers to JIRA-1337
+BREAKING CHANGE: ticket endpoints no longer supports list all entities.
+fix(shopping-cart): prevent order an empty shopping cart
+fix(api): fix wrong calculation of request body checksum
+fix: add missing parameter to service call
+The error occurred due to <reasons>.
+perf: decrease memory footprint for determine unique visitors by using HyperLogLog
+build: update dependencies
+build(release): bump version to 1.0.0
+refactor: implement fibonacci number calculation as recursion
+style: remove empty line
 
 {{ diff_text }}{{ context }}