Most German docs were written with `ue`/`ae`/`oe`/`ss` ASCII fallbacks
(`fuer`, `aenderung`, `koennen`, `gemaess`) — relic from older toolchain
constraints. Replaced 237 occurrences across 38 .md files with proper
umlauts and ß so the docs read naturally.
Substitutions are constrained to plain prose: fenced code blocks
(```...```), inline code spans (`...`), markdown link targets `[..](..)`,
and HTML comments are preserved verbatim. Path references like
`docs/howto-erste-aenderung.md` keep their original (umlaut-replaced)
filenames — only the surrounding prose is normalised.
Tool: bin/fix-md-umlauts.py (idempotent — no-op on already-clean files).
Re-runnable if ASCII fallbacks creep back in via copy-paste.
Doc-link-check + doc-drift-check stay green.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
New explanation page covers full session lifecycle: idle/absolute timeouts,
remember-token mechanics, frontend keepalive, and cookie attributes.
Updates rate limiting docs with remember-token limits and smoke test.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
