chore: repo scaffolding via /repo-init

Add .gitignore (Python stack + obligatory lines; /STATE.md kept local-only
until a private remote exists), CHANGELOG.md, and the Communication patterns
section in CLAUDE.md. STATE.md is gitignored — must never reach the public
open/ mirror.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01K8GmKRCdsPjWYAKWsNgeQS

CLAUDE.md

@@ -19,3 +19,19 @@ Repoet er på **brief-stadiet**. Start med `docs/BRIEF.md`.
 - Ingen GitHub — kun Forgejo (`git.fromaitochitta.com`) hvis/når publisert.
 - Ingen remote satt ennå; ingen push før operatøren bestemmer publisering.
 - Minimal-dependency: stdlib-first kjerne; ML/judge-detektorer bak extras.
+
+## Communication patterns
+
+### Linking to local files
+
+When pointing to local files in responses, always use markdown link syntax with a descriptive name:
+
+- Use `[Human-friendly name](file:///absolute/path)` — never bare `file:///...` URLs or autolinks `<file://...>`.
+- Always use absolute paths. Never `~/` or relative paths.
+- For multiple files, render as a bullet list of named markdown links.
+
+Why: bare `file://` URLs only render the first as clickable across multiple lines. Named markdown links make each entry independently clickable and look cleaner.
+
+Example:
+
+- [Brief](file:///Users/ktg/repos/llm-ingestion-pipeline-security/docs/BRIEF.md)