Pablan, as it stands

Self-hosted knowledge management for SMEs: a split-screen Markdown editor
whose sections an LLM refines while you write, and RAG question answering
over the documents that result. FastAPI + Postgres/pgvector on the back,
SvelteKit on the front, everything OpenAI-compatible and self-hostable.

Squashed into a single commit; the development history stays local.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CA43ZJda8Rbp2hKXNy8f6b

docs/diagrams/README.md

@@ -0,0 +1,24 @@
+# Architecture diagrams
+
+Hand-authored SVG, one per subject. The SVG **is** the artifact: no diagram
+toolchain, no build step, and it renders anywhere a browser or an IDE preview
+does. Each file carries its own stylesheet and follows the reader's light or
+dark mode through `prefers-color-scheme`.
+
+**Maintenance rule:** diagrams are as-is documentation like the rest of
+`docs/`. When a change lands that affects them, the diagram is edited in the
+same change: a stale diagram is a bug. Where docs and code disagree, the code
+wins and the doc gets fixed in the same commit.
+
+**Editing:** every box is a `<rect>` plus its `<text>` lines at explicit
+coordinates on a plain grid, so a label change is a text edit and a new box is
+a copied block with new numbers. Keep the shared `<style>` block identical
+across the five files so they stay one visual system.
+
+| Diagram | Shows |
+|---|---|
+| [data-model.svg](data-model.svg) | ER diagram of all 13 tables, FK semantics, uniques (mirrors the actual migrations) |
+| [components.svg](components.svg) | System components and their dependencies; built vs. planned (dashed) |
+| [auth-sequence.svg](auth-sequence.svg) | Login (argon2, session row, httpOnly cookie) and per-request validation incl. the 401 to redirect branch |
+| [queue-sequence.svg](queue-sequence.svg) | Job queue: claim via FOR UPDATE SKIP LOCKED, handler inside the open claim transaction, backoff, crash safety |
+| [retrieval-sequence.svg](retrieval-sequence.svg) | Hybrid retrieval, the text-only fallback, and the similarity path: permission CTE first in every one of them |