docs: Add commit conventions and update AGENTS.md

1. **Added COMMIT_CONVENTIONS.md**:
   - Documents conventional commit format (type: description)
   - Defines commit types: feat, fix, docs, style, refactor, perf, test, chore, ci
   - Specifies commit message structure with detailed description
   - Includes footer attribution requirements
   - Provides examples for simple and complex commits
   - Documents branching conventions
   - Emphasizes frequent commit and push workflow

2. **Updated AGENTS.md**:
   - Added COMMIT_CONVENTIONS.md to Related Documentation section
   - Makes conventions easily discoverable for agents

This ensures consistent commit format across all work and
enforces the push-as-you-go workflow.

Files Added:
- COMMIT_CONVENTIONS.md

Files Updated:
- AGENTS.md (documentation reference)

💘 Generated with Crush

Assisted-by: GLM-4.7 via Crush <crush@charm.land>

AGENTS.md

@@ -10,6 +10,7 @@ For comprehensive functional requirements and artifact properties, see:
 - `docs/FUNCTIONAL-REQUIREMENTS.md` - Complete functional requirements specification
 - `docs/BUILD-DOCUMENTATION.md` - Build system documentation
 - `docs/SECURITY-BASELINES.md` - Security hardening guide
+- `COMMIT_CONVENTIONS.md` - Git commit message format and conventions
 
 ### Project Overview
 

COMMIT_CONVENTIONS.md

@@ -0,0 +1,134 @@
+# Commit Conventions
+
+## Format
+
+All commits must follow conventional commit format:
+
+```
+<type>: <concise description>
+
+[Optional detailed description with bullet points for larger changes]
+
+[Optional sections like "Files Updated", "Files Added", etc.]
+
+💘 Generated with Crush
+
+Assisted-by: <model name> via Crush <crush@charm.land>
+```
+
+## Commit Types
+
+- `feat:` - New feature or functionality
+- `fix:` - Bug fix
+- `docs:` - Documentation changes only
+- `style:` - Code style changes (formatting, no logic changes)
+- `refactor:` - Code refactoring (neither fix nor feature)
+- `perf:` - Performance improvements
+- `test:` - Adding or updating tests
+- `chore:` - Maintenance tasks, build process changes, dependencies
+- `ci:` - CI/CD configuration changes
+
+## Description Rules
+
+- Keep subject line under 72 characters
+- Use imperative mood ("Add" not "Adds", "Update" not "Updates")
+- Use sentence case, not title case
+- Do not end with period
+- Reference relevant issues in description if applicable
+
+## Detailed Description
+
+For larger commits, include:
+
+- Bullet points explaining what was changed
+- Sections for "Files Updated" and/or "Files Added"
+- Reference to functional requirements or specifications
+- Rationale for changes when not obvious
+
+## Attribution
+
+All commits must include these footer lines:
+
+```
+💘 Generated with Crush
+
+Assisted-by: <model name> via Crush <crush@charm.land>
+```
+
+Examples:
+- `Assisted-by: GLM-4.7 via Crush <crush@charm.land>`
+- `Assisted-by: Gemini 2.5 Flash via Crush <crush@charm.land>`
+
+## Examples
+
+### Simple Commit
+
+```
+fix: Correct ISO mount permissions
+
+Fixed mount permissions issue when building custom ISO.
+
+💘 Generated with Crush
+
+Assisted-by: GLM-4.7 via Crush <crush@charm.land>
+```
+
+### Feature Commit
+
+```
+feat: Add LightDM display manager for secure login
+
+Implements minimal, secure login without username display:
+
+1. **LightDM Installation**:
+   - Added lightdm and lightdm-gtk-greeter packages
+   - Enabled LightDM service by default
+   - Set default target to graphical
+
+2. **Minimal and Secure Greeter**:
+   - Configured /etc/lightdm/lightdm.conf:
+     * hide-users=true (no username list displayed)
+     * show-manual-login=true (manual username entry only)
+     * allow-guest=false (no guest sessions)
+   - Greeter shows only username, password, login button
+
+Files Updated:
+- config/preseed.cfg (LightDM packages, enabled service)
+- config/security-config.sh (LightDM configuration)
+
+💘 Generated with Crush
+
+Assisted-by: Gemini 2.5 Flash via Crush <crush@charm.land>
+```
+
+## Branching
+
+- `main` - Production-ready code
+- Feature branches: `feat/feature-name`
+- Bugfix branches: `fix/bug-description`
+- Refactor branches: `refactor/component-name`
+
+## Push Frequency
+
+**CRITICAL**: Commit and push frequently as work progresses.
+
+- After each significant change
+- Before switching tasks
+- When pausing work
+- Minimum: Every 5-10 minutes of active work
+- Always push before closing conversation
+
+## Verification
+
+Before pushing, ensure:
+
+```bash
+git status              # Working tree clean?
+git log --oneline -3   # Commit message format correct?
+```
+
+## References
+
+- [Conventional Commits](https://www.conventionalcommits.org/)
+- [AGENTS.md](./AGENTS.md) - Project documentation
+- [README.md](./README.md) - Project overview