Initial release: full Arma 3 mod management toolchain

Pipeline: parse HTML presets, compare modlists, download from Caddy
file server, create junctions/symlinks to Arma 3 Server directory.
Includes update/sync flows, missing-mod reporting, OS compat layer,
shared config, dep checker, comprehensive test suite (71 tests).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

arma_modlist_tools/config.py

@@ -0,0 +1,109 @@
+"""
+arma_modlist_tools.config
+~~~~~~~~~~~~~~~~~~~~~~~~~
+Load and expose project configuration from ``config.json``.
+
+Search order for the config file:
+  1. Explicit path passed to :func:`load_config`
+  2. ``config.json`` in the current working directory
+  3. ``config.json`` two levels above this module (project root)
+
+Typical usage::
+
+    from arma_modlist_tools.config import load_config
+
+    cfg = load_config()
+    print(cfg.server_url)
+    print(cfg.arma_dir)
+"""
+
+from __future__ import annotations
+
+import json
+from pathlib import Path
+
+
+class Config:
+    """Typed wrapper around the parsed ``config.json`` dict."""
+
+    def __init__(self, data: dict) -> None:
+        # Validate required keys immediately so callers get a clear error at
+        # load time rather than a confusing AttributeError deep in the pipeline.
+        _ = data["server"]["base_url"]
+        _ = data["server"]["username"]
+        _ = data["server"]["password"]
+        _ = data["paths"]["arma_dir"]
+        _ = data["paths"]["downloads"]
+        _ = data["paths"]["modlist_html"]
+        _ = data["paths"]["modlist_json"]
+        self._data = data
+
+    # ---- server ----
+
+    @property
+    def server_url(self) -> str:
+        return self._data["server"]["base_url"]
+
+    @property
+    def server_auth(self) -> tuple[str, str]:
+        return (self._data["server"]["username"], self._data["server"]["password"])
+
+    # ---- paths ----
+
+    @property
+    def arma_dir(self) -> Path:
+        return Path(self._data["paths"]["arma_dir"])
+
+    @property
+    def downloads(self) -> Path:
+        return Path(self._data["paths"]["downloads"])
+
+    @property
+    def modlist_html(self) -> Path:
+        return Path(self._data["paths"]["modlist_html"])
+
+    @property
+    def modlist_json(self) -> Path:
+        return Path(self._data["paths"]["modlist_json"])
+
+    # ---- derived paths ----
+
+    @property
+    def comparison(self) -> Path:
+        return self.modlist_json / "comparison.json"
+
+    @property
+    def missing_report(self) -> Path:
+        return self.modlist_json / "missing_report.json"
+
+
+def load_config(path: Path | str | None = None) -> Config:
+    """
+    Load ``config.json`` and return a :class:`Config` instance.
+
+    :param path: Explicit path to the config file. If ``None``, the function
+                 searches the current working directory then the project root.
+    :raises FileNotFoundError: If no config file can be located.
+    :raises KeyError: If required keys are absent from the config file.
+    """
+    if path is not None:
+        config_path = Path(path)
+    else:
+        # Try CWD first, then project root (two levels above this file)
+        cwd_path  = Path.cwd() / "config.json"
+        root_path = Path(__file__).parent.parent / "config.json"
+        if cwd_path.exists():
+            config_path = cwd_path
+        elif root_path.exists():
+            config_path = root_path
+        else:
+            raise FileNotFoundError(
+                "config.json not found. "
+                f"Looked in:\n  {cwd_path}\n  {root_path}\n"
+                "Create config.json in the project root (copy from the template)."
+            )
+
+    with open(config_path, encoding="utf-8") as f:
+        data = json.load(f)
+
+    return Config(data)