refactor: introduce REPO_ROOT in core.py, replace all CWD-relative paths

Defines REPO_ROOT = Path(__file__).parents[3] once in core.py.
Replaces Path(__file__).parent.parent...parent chains and Path("data/...")
CWD-relative references in admin/routes.py, content/__init__.py,
content/routes.py, and worker.py (4x local repo_root variables).

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

web/src/padelnomics/admin/routes.py

@@ -27,6 +27,7 @@ from quart import (
 from ..auth.routes import role_required
 from ..core import (
     EMAIL_ADDRESSES,
+    REPO_ROOT,
     config,
     count_where,
     csrf_protect,
@@ -2182,7 +2183,7 @@ async def scenario_pdf(scenario_id: int):
 # Article Management
 # =============================================================================
 
-_ARTICLES_DIR = Path(__file__).parent.parent.parent.parent.parent / "data" / "content" / "articles"
+_ARTICLES_DIR = REPO_ROOT / "content" / "articles"
 _FRONTMATTER_RE = re.compile(r"^---\s*\n(.*?)\n---\s*\n", re.DOTALL)
 
 
@@ -2780,7 +2781,7 @@ async def article_new():
         (build_dir / f"{article_slug}.html").write_text(body_html)
 
         # Save markdown source
-        md_dir = Path("data/content/articles")
+        md_dir = REPO_ROOT / "content" / "articles"
         md_dir.mkdir(parents=True, exist_ok=True)
         (md_dir / f"{article_slug}.md").write_text(body)
 
@@ -2851,7 +2852,7 @@ async def article_edit(article_id: int):
             build_dir.mkdir(parents=True, exist_ok=True)
             (build_dir / f"{article['slug']}.html").write_text(body_html)
 
-            md_dir = Path("data/content/articles")
+            md_dir = REPO_ROOT / "content" / "articles"
             md_dir.mkdir(parents=True, exist_ok=True)
             (md_dir / f"{article['slug']}.md").write_text(body)
 
@@ -3042,7 +3043,7 @@ async def _rebuild_article(article_id: int):
         )
     else:
         # Manual article: re-render from markdown file
-        md_path = Path("data/content/articles") / f"{article['slug']}.md"
+        md_path = REPO_ROOT / "content" / "articles" / f"{article['slug']}.md"
         if not md_path.exists():
             return
         raw = md_path.read_text()

web/src/padelnomics/content/__init__.py

@@ -17,14 +17,14 @@ import yaml
 from jinja2 import ChainableUndefined, Environment
 
 from ..analytics import fetch_analytics
-from ..core import slugify, transaction, utcnow_iso
+from ..core import REPO_ROOT, slugify, transaction, utcnow_iso
 
 logger = logging.getLogger(__name__)
 
 # ── Constants ────────────────────────────────────────────────────────────────
 
 TEMPLATES_DIR = Path(__file__).parent / "templates"
-BUILD_DIR = Path("data/content/_build")
+BUILD_DIR = REPO_ROOT / "data" / "content" / "_build"
 
 # Threshold functions per template slug.
 # Return True → article should be noindex (insufficient data for quality content).

web/src/padelnomics/content/routes.py

@@ -9,7 +9,14 @@ from jinja2 import Environment, FileSystemLoader
 from markupsafe import Markup
 from quart import Blueprint, abort, g, redirect, render_template, request
 
-from ..core import capture_waitlist_email, csrf_protect, feature_gate, fetch_all, fetch_one
+from ..core import (
+    REPO_ROOT,
+    capture_waitlist_email,
+    csrf_protect,
+    feature_gate,
+    fetch_all,
+    fetch_one,
+)
 from ..i18n import get_translations
 
 bp = Blueprint(
@@ -18,7 +25,7 @@ bp = Blueprint(
     template_folder=str(Path(__file__).parent / "templates"),
 )
 
-BUILD_DIR = Path("data/content/_build")
+BUILD_DIR = REPO_ROOT / "data" / "content" / "_build"
 
 RESERVED_PREFIXES = (
     "/admin", "/auth", "/planner", "/billing", "/dashboard",

web/src/padelnomics/core.py

@@ -27,6 +27,9 @@ from quart import g, make_response, render_template, request, session  # noqa: E
 
 load_dotenv()
 
+# Repo root: web/src/padelnomics/core.py → 4 levels up
+REPO_ROOT = Path(__file__).parents[3]
+
 
 def _env(key: str, default: str) -> str:
     """Get env var, treating empty string same as unset."""

web/src/padelnomics/worker.py

@@ -11,6 +11,7 @@ from datetime import datetime, timedelta
 
 from .core import (
     EMAIL_ADDRESSES,
+    REPO_ROOT,
     config,
     execute,
     fetch_all,
@@ -710,9 +711,8 @@ async def handle_run_extraction(payload: dict) -> None:
       If absent, runs all extractors via the umbrella `extract` entry point.
     """
     import subprocess
-    from pathlib import Path
 
-    repo_root = Path(__file__).resolve().parents[4]
+    repo_root = REPO_ROOT
     extractor = payload.get("extractor", "").strip()
     if extractor:
         cmd_name = f"extract-{extractor.replace('_', '-')}"
@@ -743,9 +743,8 @@ async def handle_run_transform(payload: dict) -> None:
     2-hour absolute timeout — same as extraction.
     """
     import subprocess
-    from pathlib import Path
 
-    repo_root = Path(__file__).resolve().parents[4]
+    repo_root = REPO_ROOT
     result = await asyncio.to_thread(
         subprocess.run,
         ["uv", "run", "sqlmesh", "-p", "transform/sqlmesh_padelnomics", "plan", "prod", "--auto-apply"],
@@ -769,9 +768,8 @@ async def handle_run_export(payload: dict) -> None:
     10-minute absolute timeout.
     """
     import subprocess
-    from pathlib import Path
 
-    repo_root = Path(__file__).resolve().parents[4]
+    repo_root = REPO_ROOT
     result = await asyncio.to_thread(
         subprocess.run,
         ["uv", "run", "python", "src/padelnomics/export_serving.py"],
@@ -791,9 +789,8 @@ async def handle_run_export(payload: dict) -> None:
 async def handle_run_pipeline(payload: dict) -> None:
     """Run full ELT pipeline: extract → transform → export, stopping on first failure."""
     import subprocess
-    from pathlib import Path
 
-    repo_root = Path(__file__).resolve().parents[4]
+    repo_root = REPO_ROOT
 
     steps = [
         (