feat(dashboard): entity list UX — REF column, name cells, detail pages (CUST-WP-0030)

- ref-cell.js: REF column component — click=copy deeplink, dblclick=open
- field-help.js: field registry + fieldRow helper with help-tip decoration;
  FK fields (task_id, workstream_id, repo_id) render as async-linked cells
  with entity-title bubble-help on hover
- GET /token-events/{id} endpoint + get-by-id tests
- GET /repos/by-id/{repo_id} UUID lookup endpoint
- Landing pages: /token-events/[id], /workstreams/[id], /repos/[slug], /tasks/[id]
- token-cost.md: REF + Name columns on all three tables; parallel fetch of
  workstreams/tasks for title resolution
- reference.md: entity detail page URL scheme documented

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

dashboard/src/data/repos/[slug].json.py

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+#!/usr/bin/env python3
+"""Observable data loader: fetches a single repo by slug."""
+import json
+import os
+import sys
+import urllib.request
+import urllib.error
+
+API_BASE = os.environ.get("API_BASE", "http://127.0.0.1:8000").rstrip("/")
+
+slug = sys.argv[1] if len(sys.argv) > 1 else ""
+
+if not slug:
+    print(json.dumps({"error": "No repo slug provided"}))
+    sys.exit(1)
+
+try:
+    with urllib.request.urlopen(f"{API_BASE}/repos/{slug}/", timeout=10) as resp:
+        data = json.loads(resp.read())
+    print(json.dumps(data))
+except urllib.error.HTTPError as e:
+    if e.code == 404:
+        print(json.dumps({"error": f"Repo {slug!r} not found"}))
+        sys.exit(1)
+    print(json.dumps({"error": f"HTTP {e.code}: {e.reason}"}))
+    sys.exit(1)
+except urllib.error.URLError as e:
+    print(json.dumps({"error": str(e)}))
+    sys.exit(1)

dashboard/src/data/token-events/[id].json.py

@@ -0,0 +1,29 @@
+#!/usr/bin/env python3
+"""Observable data loader: fetches a single token event by ID."""
+import json
+import os
+import sys
+import urllib.request
+import urllib.error
+
+API_BASE = os.environ.get("API_BASE", "http://127.0.0.1:8000").rstrip("/")
+
+event_id = sys.argv[1] if len(sys.argv) > 1 else ""
+
+if not event_id:
+    print(json.dumps({"error": "No event ID provided"}))
+    sys.exit(1)
+
+try:
+    with urllib.request.urlopen(f"{API_BASE}/token-events/{event_id}", timeout=10) as resp:
+        data = json.loads(resp.read())
+    print(json.dumps(data))
+except urllib.error.HTTPError as e:
+    if e.code == 404:
+        print(json.dumps({"error": f"Token event {event_id!r} not found"}))
+        sys.exit(1)
+    print(json.dumps({"error": f"HTTP {e.code}: {e.reason}"}))
+    sys.exit(1)
+except urllib.error.URLError as e:
+    print(json.dumps({"error": str(e)}))
+    sys.exit(1)

dashboard/src/data/workstreams/[id].json.py

@@ -0,0 +1,29 @@
+#!/usr/bin/env python3
+"""Observable data loader: fetches a single workstream by ID."""
+import json
+import os
+import sys
+import urllib.request
+import urllib.error
+
+API_BASE = os.environ.get("API_BASE", "http://127.0.0.1:8000").rstrip("/")
+
+ws_id = sys.argv[1] if len(sys.argv) > 1 else ""
+
+if not ws_id:
+    print(json.dumps({"error": "No workstream ID provided"}))
+    sys.exit(1)
+
+try:
+    with urllib.request.urlopen(f"{API_BASE}/workstreams/{ws_id}", timeout=10) as resp:
+        data = json.loads(resp.read())
+    print(json.dumps(data))
+except urllib.error.HTTPError as e:
+    if e.code == 404:
+        print(json.dumps({"error": f"Workstream {ws_id!r} not found"}))
+        sys.exit(1)
+    print(json.dumps({"error": f"HTTP {e.code}: {e.reason}"}))
+    sys.exit(1)
+except urllib.error.URLError as e:
+    print(json.dumps({"error": str(e)}))
+    sys.exit(1)