fix(story-mode): appends without invented line numbers, printed files you can open, whose words start a turn

The rest of review round 5 (a phone with touch):

- Text appended with `cat >> f <<EOF` or `echo x >> f` was drawn as lines
  1 to 8 of the file; where an append lands is not in the command, so the
  diff now says "Added at the end of the file (8 lines)" with no numbers.
- A command that prints a file and does something else (`cat textstats.py
  && pytest`) kept no record of the file; it is now on the event,
  resolved against the command's own folder, and the output drawer offers
  "Open textstats.py". (A file rewritten by a python here-document still
  cannot be diffed from the command alone; Claude Code's own "modified"
  note, when it comes, is used.)
- A background job's report that starts a turn was a balloon credited to
  "you" in the API (the page already drew it as a note); its speaker is
  now "note".
- The output drawer tagged a command still running in the background
  "ok"; it says "in the background".
- The Header buttons hint says that on a phone, Story Mode opens from
  Session Options.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

src/web/public/index.html

@@ -2068,7 +2068,7 @@
 
               <div class="set-group">
                 <div class="set-group-head"><h4>Header buttons</h4><span class="set-scope">device</span></div>
-                <p class="set-group-hint">Tap to show a control in the header. Multi-monitor is the one entry here that syncs across devices.</p>
+                <p class="set-group-hint">Tap to show a control in the header. Multi-monitor is the one entry here that syncs across devices. On a phone, Story Mode opens from Session Options instead.</p>
                 <div class="set-group-body">
                   <div class="set-chips" data-search="header buttons plan usage font stats lifecycle response story file viewer attachments monitor session away cron redraw split tiles">
                     <label class="set-chip" data-preview="header" data-preview-order="1" data-preview-text="A+"><input type="checkbox" id="appSettingsShowFontControls"><svg class="set-chip-ico" width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.9" stroke-linecap="round" stroke-linejoin="round" aria-hidden="true"><path d="M4 20 10 5l6 15"/><path d="M6.5 15h7"/><path d="M18 12h4M20 10v4"/></svg><span>Font Size</span></label>

src/web/public/story-mode.css

@@ -820,6 +820,11 @@ body.story-open .toast-container {
   background: var(--story-panel);
   border: 2px solid var(--story-ink);
 }
+.story-out-files {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 6px;
+}
 .story-df-head,
 .story-out-head {
   position: sticky;

src/web/public/story-mode.js

@@ -3243,7 +3243,13 @@ Object.assign(CodemanApp.prototype, {
     const code = el('div', 'story-code');
     for (const h of edit.hunks || []) {
       code.append(
-        el('div', 'story-ln story-ln--hunk', `@@ -${h.oldStart},${h.oldLines} +${h.newStart},${h.newLines} @@`)
+        el(
+          'div',
+          'story-ln story-ln--hunk',
+          h.atEnd
+            ? `Added at the end of the file (${h.newLines} ${h.newLines === 1 ? 'line' : 'lines'})`
+            : `@@ -${h.oldStart},${h.oldLines} +${h.newStart},${h.newLines} @@`
+        )
       );
       let o = h.oldStart;
       let n = h.newStart;
@@ -3251,8 +3257,8 @@ Object.assign(CodemanApp.prototype, {
         const mark = line[0];
         const row = el('div', `story-ln${mark === '+' ? ' story-ln--add' : mark === '-' ? ' story-ln--del' : ''}`);
         row.append(
-          el('span', 'story-ln-no', mark === '+' ? '' : String(o)),
-          el('span', 'story-ln-no', mark === '-' ? '' : String(n)),
+          el('span', 'story-ln-no', mark === '+' || h.atEnd ? '' : String(o)),
+          el('span', 'story-ln-no', mark === '-' || h.atEnd ? '' : String(n)),
           el('span', 'story-ln-mk', mark === '+' ? '+' : mark === '-' ? '−' : ''),
           el('span', 'story-ln-tx', line.slice(1) || ' ')
         );
@@ -3273,10 +3279,11 @@ Object.assign(CodemanApp.prototype, {
     const shown = this._storyShortPath(ev.label, { dot: ev.tool === 'Bash' });
     const cmd = el('span', 'story-out-cmd', `${ev.tool === 'Bash' ? '$ ' : `${ev.tool} `}${shown}`);
     if (ev.label !== shown) cmd.title = ev.label;
+    const waiting = ev.pending || ev.running;
     const status = el(
       'span',
-      `story-tag story-tag--${ev.ok === false ? 'bad' : ev.pending ? 'pending' : 'ok'}`,
-      ev.ok === false ? 'error' : ev.pending ? 'running' : 'ok'
+      `story-tag story-tag--${ev.ok === false ? 'bad' : waiting ? 'pending' : 'ok'}`,
+      ev.ok === false ? 'error' : ev.running ? 'in the background' : waiting ? 'running' : 'ok'
     );
     head.append(cmd, status);
     section.append(head);
@@ -3296,6 +3303,18 @@ Object.assign(CodemanApp.prototype, {
         b.dataset.storyOpen = `diff:event:${index}`;
         section.append(b);
       }
+      // Files it printed (`cat a.py`): open them as they are now.
+      if (ev.files?.length && ev.intent !== 'look') {
+        const row = el('div', 'story-out-files');
+        for (const f of ev.files.slice(0, 4)) {
+          const b = el('button', 'story-btn-s', `Open ${f.split('/').pop()}`);
+          b.type = 'button';
+          b.title = f;
+          b.addEventListener('click', (e) => this._storyOpenFile(this._storyResolvePath(f), e.currentTarget));
+          row.append(b);
+        }
+        section.append(row);
+      }
     } else if (ev.outputTruncated) {
       section.append(el('p', 'story-empty', 'This output was left out to keep a long turn fast.'));
     } else if (target && !target.startsWith('output:')) {