fix(visualize): address code-review findings

- graph.html project(): clamp the perspective denominator (FOCAL+z2) so a
  node crossing the camera plane can't divide by ~0 → ±Infinity/NaN, which
  previously flung the node off-screen and (via centerOn) poisoned panX/panY
  until reload.
- graph.html: require >4px of motion before a press counts as a drag, so a
  normal click (with sub-pixel jitter) inspects the node instead of pinning it.
- visualize.py: reuse schema.PAGE_CONTENT_DIRS instead of a local _NODE_DIRS
  copy, and derive the fallback type so a new content dir can't KeyError.
- visualize.py: read each wiki file once (cache text for the edge pass)
  instead of twice.

Author: KylinMountain

openkb/templates/graph.html

@@ -291,7 +291,7 @@
     const z1 = -n.x*syw + n.z*cyw;
     const y2 = n.y*cpt - z1*spt;           // then about X (pitch)
     const z2 = n.y*spt + z1*cpt;
-    const pp = FOCAL/(FOCAL + z2);          // perspective: near → larger
+    const pp = FOCAL/Math.max(FOCAL + z2, FOCAL*0.25);   // perspective: near→larger; clamp denom so a node crossing the camera plane can't blow up to ±Infinity/NaN
     n.rz = z2; n.pp = pp;
     n.sx = ox + x1*pp*scale;
     n.sy = oy + y2*pp*scale;
@@ -442,8 +442,11 @@
 /* ===================== hover / drag / pan ===================== */
 canvas.addEventListener("mousemove", e => {
   if(drag){
+    // ignore sub-pixel jitter so a plain click still inspects instead of pinning
+    if(!didDrag && Math.hypot(e.offsetX - oStartX, e.offsetY - oStartY) < 4) return;
+    didDrag = true;
     const w = unproject(e.offsetX, e.offsetY, drag);   // move the node within the current view plane
-    drag.x = w.x; drag.y = w.y; drag.z = w.z; drag.vx = drag.vy = drag.vz = 0; didDrag = true;
+    drag.x = w.x; drag.y = w.y; drag.z = w.z; drag.vx = drag.vy = drag.vz = 0;
     alpha = Math.max(alpha, 0.5);   // reheat so neighbors re-settle around the dragged node
     return;
   }
@@ -458,8 +461,9 @@
 canvas.addEventListener("mousedown", e => {
   const n = pick(e.offsetX, e.offsetY);
   didDrag = false;
+  oStartX = e.offsetX; oStartY = e.offsetY;   // press origin — for the drag threshold and for orbit
   if(n){ drag = n; hover = n.id; canvas.style.cursor = "grabbing"; }
-  else { orbiting = true; oStartX = e.offsetX; oStartY = e.offsetY; yawStart = yaw; pitchStart = pitch; canvas.style.cursor = "grabbing"; }
+  else { orbiting = true; yawStart = yaw; pitchStart = pitch; canvas.style.cursor = "grabbing"; }
 });
 window.addEventListener("mouseup", e => {
   if(drag && !didDrag){ openPanel(drag); }                         // click (no drag) → inspect

openkb/visualize.py

@@ -7,23 +7,32 @@
 
 from openkb import frontmatter
 from openkb.lint import _extract_wikilinks, _normalize_target
+from openkb.schema import PAGE_CONTENT_DIRS
 
-_NODE_DIRS = ("summaries", "concepts", "entities")
-_FALLBACK_TYPE = {"summaries": "Summary", "concepts": "Concept", "entities": "Entity"}
+# Singular display type per content dir; falls back to a derived name for any
+# dir not listed (so a new PAGE_CONTENT_DIRS entry never KeyErrors here).
+_DIR_TYPE = {"summaries": "Summary", "concepts": "Concept", "entities": "Entity"}
+
+
+def _type_for_dir(sub: str) -> str:
+    return _DIR_TYPE.get(sub) or sub.rstrip("s").capitalize() or sub
 
 
 def build_graph(wiki_dir: Path) -> dict:
     """Collect nodes (pages), directed edges (wikilinks), and the set of types."""
     nodes: dict[str, dict] = {}
-    for sub in _NODE_DIRS:
+    texts: dict[str, str] = {}   # nid -> file text, read once and reused for edges
+    for sub in PAGE_CONTENT_DIRS:
         d = wiki_dir / sub
         if not d.exists():
             continue
         for p in sorted(d.glob("*.md")):
             nid = f"{sub}/{p.stem}"
-            fm = frontmatter.parse(p.read_text(encoding="utf-8"))
+            text = p.read_text(encoding="utf-8")
+            texts[nid] = text
+            fm = frontmatter.parse(text)
             t = fm.get("type")
-            t = t.strip() if isinstance(t, str) and t.strip() else _FALLBACK_TYPE[sub]
+            t = t.strip() if isinstance(t, str) and t.strip() else _type_for_dir(sub)
             desc = fm.get("description")
             desc = desc.strip() if isinstance(desc, str) else ""
             srcs = fm.get("sources")
@@ -34,20 +43,15 @@ def build_graph(wiki_dir: Path) -> dict:
     norm = {_normalize_target(nid): nid for nid in nodes}
     edges: list[dict] = []
     seen: set[tuple[str, str]] = set()
-    for sub in _NODE_DIRS:
-        d = wiki_dir / sub
-        if not d.exists():
-            continue
-        for p in sorted(d.glob("*.md")):
-            src = f"{sub}/{p.stem}"
-            for raw in _extract_wikilinks(p.read_text(encoding="utf-8")):
-                tgt = norm.get(_normalize_target(raw))
-                if not tgt or tgt == src or (src, tgt) in seen:
-                    continue
-                seen.add((src, tgt))
-                edges.append({"source": src, "target": tgt})
-                nodes[src]["out"] += 1
-                nodes[tgt]["in"] += 1
+    for src, text in texts.items():
+        for raw in _extract_wikilinks(text):
+            tgt = norm.get(_normalize_target(raw))
+            if not tgt or tgt == src or (src, tgt) in seen:
+                continue
+            seen.add((src, tgt))
+            edges.append({"source": src, "target": tgt})
+            nodes[src]["out"] += 1
+            nodes[tgt]["in"] += 1
 
     types = sorted({n["type"] for n in nodes.values()})
     return {"nodes": list(nodes.values()), "edges": edges, "types": types}