Add document converter, seeder data structure, and project wiki

- ai-service/convert.py: converts Office/PDF files to markdown with frontmatter
- database/seeders/data/: folder structure for themas, projects, documents, etc.
- database/seeders/data/raw/: drop zone for Office/PDF files to convert
- wiki/: project architecture, concepts, and knowledge graph documentation
- Remove unused Laravel example tests

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

wiki/log.md

@@ -0,0 +1,11 @@
+---
+title: Wiki Log
+created: 2026-04-08
+updated: 2026-04-08
+status: evolving
+tags: [log, history]
+---
+
+# Wiki Log
+
+## [2026-04-08] init | Wiki initialized from wiki-template, populated with codebase scan data