docs: replace stub README, add proper README and CHANGELOG per itpp-standards template

- Rewrote README.md following itpp-standards Section 2.1 template
- Updated CHANGELOG.md to standard format
- Added .gitea/workflows/docs-check.yml for docs CI

README.md

@@ -1,3 +1,23 @@
-# apex-track
+# Apex Track Experience
 
-Project directory. See CHANGELOG.md for development history.
+> **Owner:** Germaine | **Status:** PLANNED
+> **Last Updated:** 2026-08-09
+
+Apex Track is a track event and racing experience management platform. Designed for track day organizers, racing clubs, and motorsport venues to manage event scheduling, participant registration, timing and scoring, and live results publishing.
+
+## Tech Stack
+
+- TBD — architecture and stack decisions pending
+
+## Quick Start
+
+```bash
+git clone https://git.itpropartner.com/ippadmin/apex-track.git
+cd apex-track
+# Project in early planning phase — implementation to follow
+```
+
+## Related
+
+- [itpp-infrastructure](https://git.itpropartner.com/ippadmin/itpp-infrastructure) — server inventory, DNS
+- [itpp-standards](https://git.itpropartner.com/ippadmin/itpp-standards) — docs standards and templates