docs: add Sphinx documentation build and deploy workflow

- Add Gitea Actions workflow to build and deploy docs on push to main
- Generate Sphinx reference documentation for all apps and modules
- Deploy versioned and latest docs via rsync over SSH

docs/regenerate_docs.sh

@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+# Regenerate Sphinx API reference for every Mnemosyne app, then build HTML.
+# Drives both local development and the CI pipeline.
+set -euo pipefail
+
+cd "$(dirname "$0")"
+
+APPS=(themis library llm_manager mcp_server)
+SOURCE_REF=source/reference/apps
+PACKAGE_ROOT=../mnemosyne
+
+make clean
+
+mkdir -p "$SOURCE_REF"
+
+# Per-app subdir so each app gets its own modules.rst (sphinx-apidoc
+# overwrites the file otherwise, leaving only the last app in the index).
+for app in "${APPS[@]}"; do
+    sphinx-apidoc \
+        --force \
+        --separate \
+        --module-first \
+        --output-dir "$SOURCE_REF/$app" \
+        "$PACKAGE_ROOT/$app" \
+        "$PACKAGE_ROOT/$app/migrations" \
+        "$PACKAGE_ROOT/$app/tests"
+done
+
+# Write a top-level apps.rst that toctree's every app's modules.rst.
+{
+    echo "Applications"
+    echo "============"
+    echo
+    echo ".. toctree::"
+    echo "   :maxdepth: 2"
+    echo
+    for app in "${APPS[@]}"; do
+        echo "   $app/modules"
+    done
+} > "$SOURCE_REF/index.rst"
+
+make html