dashboard: move live indicator to TOC sidebar on all pages; add live-data docs

- All four pages (index, workstreams, decisions, progress) now inject the
  live indicator into #observablehq-toc via injectTocTop("live-indicator", el)
  Left-aligned (no text-align: right), position:relative + padding-right for
  the ? button affordance

- decisions.md: splits the former combined "decisions-sidebar" widget into two
  separate injectTocTop calls — KPI box first (ends lower), live indicator
  second (ends at top); both now have their own stable ids

- withDocHelp(_liveEl, "/docs/live-data") wires the ? button on every page

- src/docs/live-data.md: new documentation page explaining poll interval (15s),
  indicator colour semantics, offline recovery, and which endpoints each page hits

- Removes the .live-bar CSS class from all pages; replaces with .live-indicator

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

dashboard/src/progress.md

@@ -33,12 +33,17 @@ const _ts  = progState.ts;
 *Append-only per constitution §5 — no deletions.*
 
 ```js
-display(html`<div class="live-bar">
+import {injectTocTop} from "./components/toc-sidebar.js";
+import {withDocHelp}   from "./components/doc-overlay.js";
+
+const _liveEl = html`<div class="live-indicator">
   <span style="color:${_ok ? 'var(--theme-foreground-focus)' : 'red'}">●</span>
   ${_ok
     ? `Live · updated ${_ts?.toLocaleTimeString()} · ${data.length} events total`
-    : `<span style="color:red">Offline — run: <code>make api</code></span>`}
-</div>`);
+    : html`<span style="color:red">Offline — run: <code>make api</code></span>`}
+</div>`;
+withDocHelp(_liveEl, "/docs/live-data");
+injectTocTop("live-indicator", _liveEl);
 ```
 
 ```js
@@ -101,5 +106,5 @@ display(byDay.length === 0
 ```
 
 <style>
-.live-bar { font-size: 0.8rem; color: gray; text-align: right; margin-bottom: 0.5rem; }
+.live-indicator { font-size: 0.8rem; color: gray; margin-bottom: 0.75rem; position: relative; padding-right: 1.6rem; }
 </style>