docs: drop leftover 'nothing nests' framing from C0NTAINERS blurb

Per mara's review on #4769: don't extend stale info to say it's stale,
just remove it. The sentence only described the absence of the removed
topology tree, giving the operator nothing actionable.

docs/web-ui/README.md

@@ -115,8 +115,7 @@ touching the code rather than using the UI:
   [`shape.md`](shape.md) (SSE multiplexing, Worker-death self-heal,
   atomic repaint).
 - **"What does a container row contain?"** →
-  [`dashboard.md`](dashboard.md) (Container row, Topology tree,
-  Selection bar).
+  [`dashboard.md`](dashboard.md) (Container row, Selection bar).
 - **"What endpoints does the dashboard expose?"** →
   [`dashboard.md`](dashboard.md) (Dashboard endpoints, Dashboard event
   channel).

docs/web-ui/dashboard.md

@@ -57,8 +57,7 @@ surfaces, not tab panes.
 ## SW4RM tab
 
 **C0NTAINERS** — live containers as a flat list, one row per
-container, sorted alphabetically by agent name. No row nests under
-another, none carries an indent or a tree glyph, and every container the
+container, sorted alphabetically by agent name; every container the
 rescan reports gets a row. Pulsing red banner at the top
 of this section if any two sub-agents hash to the same port
 (`port_conflicts` from `/api/state`): the operator must rename
@@ -974,14 +973,6 @@ build. (The `hivectl stop --graceful` CLI flag enqueues the same
 `Signal`/`Drain` pair, so the dashboard and CLI paths behave
 identically.)
 
-### Topology tree
-
-Nothing nests. `swarm.js::buildAgentTree` returns every container at
-depth 0 in alphabetical order, and the row builder emits no prefix
-column for a depth-0 row — so a container row carries no indent, no
-joint and no continuation bar, and the SW4RM list reads as a flat
-roster. The `.tree-prefix` lane rules in `dashboard.css` match nothing.
-
 ## Selection bar
 
 Bulk actions (`R3ST4RT` / `ST0P` / `ST4RT` / `P4US3` / `R3SUM3` /

frontend/packages/dashboard/src/dashboard.css

@@ -200,84 +200,6 @@ body.dashboard-shell {
     opacity 200ms ease,
     border-color 200ms ease;
 }
-/* Topology indent ladder. See docs/web-ui/dashboard.md::Topology tree (Indent
-   + lane geometry paragraph) for the 1.8em-per-depth-level
-   rationale + CSS-attr()-not-yet-portable caveat. */
-.container-row[data-depth] {
-  position: relative;
-}
-.container-row[data-depth="1"] {
-  margin-left: 1.8em;
-}
-.container-row[data-depth="2"] {
-  margin-left: 3.6em;
-}
-.container-row[data-depth="3"] {
-  margin-left: 5.4em;
-}
-.container-row[data-depth="4"] {
-  margin-left: 7.2em;
-}
-.container-row[data-depth="5"] {
-  margin-left: 9em;
-}
-.container-row[data-depth="6"] {
-  margin-left: 10.8em;
-}
-/* Tree prefix lanes — DOM-painted, not text-glyph-painted. */
-.container-row .tree-prefix {
-  position: absolute;
-  top: 0;
-  bottom: -0.4em;
-  display: flex;
-  flex-direction: row;
-  pointer-events: none;
-  user-select: none;
-  color: var(--purple-dim);
-}
-.container-row[data-depth="1"] .tree-prefix {
-  left: -1.8em;
-}
-.container-row[data-depth="2"] .tree-prefix {
-  left: -3.6em;
-}
-.container-row[data-depth="3"] .tree-prefix {
-  left: -5.4em;
-}
-.container-row[data-depth="4"] .tree-prefix {
-  left: -7.2em;
-}
-.container-row[data-depth="5"] .tree-prefix {
-  left: -9em;
-}
-.container-row[data-depth="6"] .tree-prefix {
-  left: -10.8em;
-}
-.tree-prefix .tree-lane {
-  flex: 0 0 1.8em;
-  position: relative;
-}
-.tree-prefix .lane-line::before,
-.tree-prefix .lane-joint::before {
-  content: "";
-  position: absolute;
-  left: 0.6em;
-  top: 0;
-  bottom: 0;
-  border-left: 1px solid currentColor;
-}
-.tree-prefix .lane-joint-last::before {
-  bottom: auto;
-  height: 3.1em;
-}
-.tree-prefix .lane-joint::after {
-  content: "";
-  position: absolute;
-  left: 0.6em;
-  top: 3.1em;
-  width: 2em;
-  border-top: 1px solid currentColor;
-}
 .container-row:not(.tombstone) {
   display: flex;
   align-items: flex-start;

frontend/packages/dashboard/src/swarm.js

@@ -226,89 +226,26 @@ function derivePortConflicts(containers) {
   return out;
 }
 
-// ─── topology tree ───────────────────────────────────────────────────────────
-// See docs/web-ui/dashboard.md::Topology tree for the rendering contract
-// (forest walk, alphabetical sort, orphan + cycle handling).
+// ─── container ordering ──────────────────────────────────────────────────────
+// Flat alphabetical sort — see docs/web-ui/dashboard.md::C0NTAINERS.
 
-function buildAgentTree(containers) {
+function sortedContainerRows(containers) {
   // Close any open context menu before replacing the DOM tree — the
   // previous dropdown element would otherwise be a stale reference.
   closeAllMenus();
-  const byName = new Map();
-  for (const c of containers) byName.set(c.name, c);
-  const children = new Map(); // parent_name -> [child_name, ...]
-  const roots = [];
-  for (const c of containers) {
-    const p = c.parent || null;
-    if (p == null || !byName.has(p)) {
-      roots.push(c.name);
-    } else {
-      const list = children.get(p) || [];
-      list.push(c.name);
-      children.set(p, list);
-    }
-  }
-  roots.sort();
-  for (const list of children.values()) list.sort();
-  const out = [];
-  const visited = new Set();
-  function visit(name, depth, ancestorIsLast, isLast) {
-    if (visited.has(name)) return;
-    visited.add(name);
-    const c = byName.get(name);
-    if (!c) return;
-    out.push({
-      container: c,
-      depth,
-      ancestorIsLast: [...ancestorIsLast],
-      isLast,
-    });
-    const kids = children.get(name) || [];
-    kids.forEach((kid, i) =>
-      visit(kid, depth + 1, [...ancestorIsLast, isLast], i === kids.length - 1),
-    );
-  }
-  roots.forEach((name, i) => visit(name, 0, [], i === roots.length - 1));
-  // Cycle safety: anything not reached lands at root level so no
-  // agent silently disappears when a config is malformed.
-  for (const c of containers) {
-    if (!visited.has(c.name)) visit(c.name, 0, [], true);
-  }
-  return out;
-}
-// Builds the .tree-prefix DOM for a row at the given depth.
-// See docs/web-ui/dashboard.md::Topology tree for why this is DOM-painted
-// (one positioned <span> per lane) rather than text-glyph-painted.
-function treePrefixDom({ depth, ancestorIsLast, isLast }) {
-  if (depth === 0) return null;
-  const prefix = el("span", { class: "tree-prefix", "aria-hidden": "true" });
-  // Ancestor columns (depth 1..depth-1). Skip depth 0 (root has no
-  // continuation column — top-level rows are separated visually as
-  // top-level rows already).
-  for (let d = 1; d < depth; d++) {
-    const cls = ancestorIsLast[d]
-      ? "tree-lane lane-blank"
-      : "tree-lane lane-line";
-    prefix.append(el("span", { class: cls }));
-  }
-  const jointCls =
-    "tree-lane lane-joint " +
-    (isLast ? "lane-joint-last" : "lane-joint-branch");
-  prefix.append(el("span", { class: jointCls }));
-  return prefix;
+  return [...containers].sort((a, b) => a.name.localeCompare(b.name));
 }
 
 // ─── container row ───────────────────────────────────────────────────────────
 
 // Serialise the visible state of a container row into a stable string
 // for change-detection. Includes everything that affects what the row
-// renders — container fields, derived pending/selection state, tree
-// position, and link-base context. The async dashboard-state (nav
-// strip, ctx badge, status text) is intentionally excluded: it
-// populates in-place and is preserved when a row is reused.
+// renders — container fields, derived pending/selection state, and
+// link-base context. The async dashboard-state (nav strip, ctx badge,
+// status text) is intentionally excluded: it populates in-place and is
+// preserved when a row is reused.
 function containerRowFingerprint(
   c,
-  node,
   pending,
   opRunning,
   selected,
@@ -326,9 +263,6 @@ function containerRowFingerprint(
     pending,
     opRunning,
     selected,
-    depth: node.depth,
-    isLast: node.isLast,
-    ancestorIsLast: node.ancestorIsLast,
     gatewayLinks,
     hostname,
   });
@@ -338,7 +272,7 @@ function containerRowFingerprint(
 // renderContainers can call this only for rows whose fingerprint
 // changed (keyed cache), skipping the build + async dashboard-state
 // fetch for stable rows.
-function buildContainerLi(c, node, opts) {
+function buildContainerLi(c, opts) {
   const { pending, opRunning, selected, url, containerBase, forgeBase, s } =
     opts;
   // A single `pending-running` class covers any active transient
@@ -350,13 +284,6 @@ function buildContainerLi(c, node, opts) {
       (opRunning ? " pending-running" : "") +
       (selected ? " selected" : ""),
   });
-  // Topology: depth contributes left-padding; the glyph string in
-  // the .tree-prefix span draws the ├─ / └─ joint + continuation
-  // lines (`│  `) for ancestors whose subtree extends below this
-  // row. A depth-0 row gets neither — no glyph, no indent.
-  if (node.depth > 0) li.dataset.depth = String(node.depth);
-  const prefix = treePrefixDom(node);
-  if (prefix) li.prepend(prefix);
 
   // Agent icon: 5em square wrapper with an absolutely-positioned
   // <img> + fire-and-forget load with /favicon.svg fallback. The
@@ -744,13 +671,12 @@ export function renderContainers(s) {
   // rather than emit a possibly-wrong one.
   const forgeBase = (s && s.forge_public_url) || null;
   const ul = existingUl ?? el("ul", { class: "containers" });
-  const tree = buildAgentTree(containers);
+  const rows = sortedContainerRows(containers);
 
   // Build the ordered list of <li> elements, reusing cached rows
   // whose displayed state hasn't changed.
   const orderedLis = [];
-  for (const node of tree) {
-    const c = node.container;
+  for (const c of rows) {
     const url = gatewayLinks
       ? `/agent/${encodeURIComponent(c.name)}/`
       : `http://${hostname}:${c.port}/`;
@@ -774,7 +700,6 @@ export function renderContainers(s) {
 
     const fp = containerRowFingerprint(
       c,
-      node,
       pending,
       opRunning,
       selected,
@@ -790,7 +715,7 @@ export function renderContainers(s) {
       // intact from the previous build, avoiding a redundant fetch.
       li = cached.el;
     } else {
-      li = buildContainerLi(c, node, {
+      li = buildContainerLi(c, {
         pending,
         opRunning,
         selected,