chore: initialize EverOS 1.0.0

md-first memory extraction framework for AI agents.

Markdown is the single source of truth; SQLite holds state and LanceDB
provides the rebuildable vector + BM25 + scalar index. The codebase follows
a single-direction DDD layering (entrypoints -> service -> memory -> infra,
with component / core / config cross-cutting) enforced by import-linter.

Engineering surface:
- Coding conventions in .claude/rules/ (path-scoped) and workflows in
  .claude/skills/ (/commit, /new-branch, /pr).
- GitHub Actions CI runs make lint + test + integration; pre-commit mirrors
  the gates locally (ruff, hygiene hooks, gitlint commit-msg).
- Commit messages follow Conventional Commits, enforced by gitlint.
- make lint also enforces datetime two-zone discipline and OpenAPI drift.

src/everos/component/config/loader.py

@@ -0,0 +1,146 @@
+"""YAML config loader for category-organised file trees.
+
+Concept: a project keeps several *categories* of YAML config files under
+their own subdirectories — for example PromptSlot templates under
+``config/prompt_slots/<name>.yaml``. The loader:
+
+    1. registers a category → subdirectory mapping
+    2. resolves ``find(category, name)`` to ``<root>/<subdir>/<name>.yaml``
+    3. caches parsed contents until ``refresh`` is called
+
+Uses ``yaml.safe_load`` (no arbitrary tags) — PyYAML is already a project
+dependency for markdown frontmatter, so no extra cost.
+"""
+
+from __future__ import annotations
+
+from collections.abc import Mapping
+from pathlib import Path
+from typing import Any
+
+import yaml
+
+
+class YamlConfigLoader:
+    """Load YAML files organised by category subdirectories.
+
+    Usage:
+        loader = YamlConfigLoader(root=Path("src/everos/config"))
+        loader.register_category("prompt_slots")
+        # → reads <root>/prompt_slots/episode.yaml
+        meta = loader.find("prompt_slots", "episode")
+        names = loader.list("prompt_slots")
+        loader.refresh()  # next find() re-reads from disk
+
+    Cache semantics:
+        * ``find`` parses the file on first access and caches the dict.
+        * ``refresh()`` empties the entire cache.
+        * ``refresh(category)`` empties one category's entries.
+        * ``refresh(category, name)`` empties a single entry.
+    """
+
+    def __init__(
+        self,
+        root: Path,
+        categories: Mapping[str, str | None] | None = None,
+    ) -> None:
+        """
+        Args:
+            root: Base directory containing the category subdirectories.
+            categories: Optional pre-registered category map (``name → subdir``).
+                When ``subdir`` is ``None`` the category name is used as-is.
+        """
+        self._root = Path(root)
+        self._subdirs: dict[str, str] = {}
+        self._cache: dict[tuple[str, str], dict[str, Any]] = {}
+
+        if categories:
+            for name, subdir in categories.items():
+                self.register_category(name, subdir)
+
+    # ── Category management ────────────────────────────────────────────────
+
+    def register_category(self, name: str, subdir: str | None = None) -> None:
+        """Register a category. ``subdir`` defaults to ``name``."""
+        self._subdirs[name] = subdir if subdir is not None else name
+
+    def categories(self) -> list[str]:
+        """Return registered category names (sorted)."""
+        return sorted(self._subdirs)
+
+    # ── Lookup ─────────────────────────────────────────────────────────────
+
+    def find(self, category: str, name: str) -> dict[str, Any]:
+        """Load ``<root>/<subdir>/<name>.yaml`` for ``category``.
+
+        Raises:
+            KeyError: if ``category`` was not registered.
+            FileNotFoundError: if the yaml file does not exist.
+            TypeError: if the parsed YAML is not a mapping.
+        """
+        cache_key = (category, name)
+        if cache_key in self._cache:
+            return self._cache[cache_key]
+
+        path = self._path_for(category, name)
+        if not path.is_file():
+            raise FileNotFoundError(f"yaml not found: {path}")
+
+        with path.open("r", encoding="utf-8") as fh:
+            data = yaml.safe_load(fh)
+        if data is None:
+            data = {}
+        if not isinstance(data, dict):
+            raise TypeError(
+                f"yaml top-level must be a mapping, got {type(data).__name__}: {path}"
+            )
+        self._cache[cache_key] = data
+        return data
+
+    def list(self, category: str) -> list[str]:
+        """Return sorted yaml stems available in ``category`` (no extension).
+
+        Raises:
+            KeyError: if ``category`` was not registered.
+        """
+        directory = self._dir_for(category)
+        if not directory.is_dir():
+            return []
+        return sorted(p.stem for p in directory.glob("*.yaml"))
+
+    # ── Cache control ──────────────────────────────────────────────────────
+
+    def refresh(
+        self,
+        category: str | None = None,
+        name: str | None = None,
+    ) -> None:
+        """Invalidate cached entries.
+
+        - ``refresh()``                  → drop every cached entry
+        - ``refresh(category)``          → drop everything in ``category``
+        - ``refresh(category, name)``    → drop a single entry
+        """
+        if category is None:
+            self._cache.clear()
+            return
+        if name is not None:
+            self._cache.pop((category, name), None)
+            return
+        self._cache = {
+            (cat, n): v for (cat, n), v in self._cache.items() if cat != category
+        }
+
+    # ── Internals ──────────────────────────────────────────────────────────
+
+    def _dir_for(self, category: str) -> Path:
+        try:
+            subdir = self._subdirs[category]
+        except KeyError as exc:
+            raise KeyError(
+                f"category not registered: {category!r}; known: {sorted(self._subdirs)}"
+            ) from exc
+        return self._root / subdir
+
+    def _path_for(self, category: str, name: str) -> Path:
+        return self._dir_for(category) / f"{name}.yaml"