feat: workspace git detection with branch/status badge

When the workspace root is a git repo, a badge in the panel header
shows the current branch name, dirty file count, and ahead/behind
status. Updates on every root directory load.

Backend:
- git_info_for_workspace() in api/workspace.py runs lightweight git
  commands (rev-parse, status --porcelain, rev-list) with 3s timeout
- New GET /api/git-info endpoint returns branch, dirty count, modified,
  untracked, ahead, behind

Frontend:
- _refreshGitBadge() in workspace.js fetches git info on root load
- Git badge element in panel header shows branch + status
- Badge turns gold when workspace has uncommitted changes

Inspired by PR #75 (@MartinNielsenDev).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

api/routes.py

@@ -214,6 +214,18 @@ def handle_get(handler, parsed):
     if parsed.path == '/api/list':
         return _handle_list_dir(handler, parsed)
 
+    if parsed.path == '/api/git-info':
+        qs = parse_qs(parsed.query)
+        sid = qs.get('session_id', [''])[0]
+        if not sid:
+            return bad(handler, 'session_id required')
+        s = get_session(sid)
+        if not s:
+            return bad(handler, 'Session not found', 404)
+        from api.workspace import git_info_for_workspace
+        info = git_info_for_workspace(Path(s.workspace))
+        return j(handler, {'git': info})
+
     if parsed.path == '/api/chat/stream/status':
         stream_id = parse_qs(parsed.query).get('stream_id', [''])[0]
         return j(handler, {'active': stream_id in STREAMS, 'stream_id': stream_id})

api/workspace.py

@@ -9,6 +9,7 @@ paths are used as fallback when no profile module is available.
 """
 import json
 import os
+import subprocess
 from pathlib import Path
 
 from api.config import (
@@ -243,3 +244,43 @@ def read_file_content(workspace: Path, rel: str):
         raise ValueError(f"File too large ({size} bytes, max {MAX_FILE_BYTES})")
     content = target.read_text(encoding='utf-8', errors='replace')
     return {'path': rel, 'content': content, 'size': size, 'lines': content.count('\n') + 1}
+
+
+# ── Git detection ──────────────────────────────────────────────────────────
+
+def _run_git(args, cwd, timeout=3):
+    """Run a git command and return stdout, or None on failure."""
+    try:
+        r = subprocess.run(
+            ['git'] + args, cwd=str(cwd), capture_output=True,
+            text=True, timeout=timeout,
+        )
+        return r.stdout.strip() if r.returncode == 0 else None
+    except (subprocess.TimeoutExpired, FileNotFoundError, OSError):
+        return None
+
+
+def git_info_for_workspace(workspace: Path) -> dict:
+    """Return git info for a workspace directory, or None if not a git repo."""
+    if not (workspace / '.git').exists():
+        return None
+    branch = _run_git(['rev-parse', '--abbrev-ref', 'HEAD'], workspace)
+    if branch is None:
+        return None
+    # Status counts
+    status_out = _run_git(['status', '--porcelain'], workspace) or ''
+    modified = sum(1 for l in status_out.splitlines() if l and l[0:2].strip() in ('M', 'MM', 'AM'))
+    untracked = sum(1 for l in status_out.splitlines() if l.startswith('??'))
+    dirty = len(status_out.splitlines()) if status_out else 0
+    # Ahead/behind
+    ahead = _run_git(['rev-list', '--count', '@{u}..HEAD'], workspace)
+    behind = _run_git(['rev-list', '--count', 'HEAD..@{u}'], workspace)
+    return {
+        'branch': branch,
+        'dirty': dirty,
+        'modified': modified,
+        'untracked': untracked,
+        'ahead': int(ahead) if ahead and ahead.isdigit() else 0,
+        'behind': int(behind) if behind and behind.isdigit() else 0,
+        'is_git': True,
+    }

static/index.html

@@ -278,6 +278,7 @@
     <div class="resize-handle" id="rightpanelResize"></div>
     <div class="panel-header">
       <span>Workspace</span>
+      <span class="git-badge" id="gitBadge" style="display:none"></span>
       <div class="panel-actions">
         <button class="panel-icon-btn" id="btnUpDir" title="Parent directory" onclick="navigateUp()" style="display:none">&#8593;</button>
         <button class="panel-icon-btn" id="btnNewFile" title="New file" onclick="promptNewFile()">&#43;</button>

static/style.css

@@ -204,6 +204,8 @@
   .upload-bar{height:100%;background:linear-gradient(90deg,var(--blue),#a0d0ff);width:0%;transition:width .3s ease;}
   .rightpanel{width:300px;background:var(--sidebar);border-left:1px solid rgba(255,255,255,.06);display:flex;flex-direction:column;overflow:hidden;flex-shrink:0;}
   .panel-header{padding:12px 16px;border-bottom:1px solid var(--border);font-size:11px;font-weight:600;color:var(--muted);text-transform:uppercase;letter-spacing:.1em;display:flex;align-items:center;justify-content:space-between;}
+  .git-badge{font-size:9px;font-weight:600;color:var(--muted);background:rgba(255,255,255,.06);padding:2px 7px;border-radius:4px;letter-spacing:.02em;margin-left:auto;margin-right:4px;white-space:nowrap;font-family:'SF Mono',ui-monospace,monospace;}
+  .git-badge.dirty{color:var(--gold);background:rgba(201,168,76,.1);}
   .panel-actions{display:flex;gap:4px;}
   .panel-icon-btn{width:24px;height:24px;background:none;border:none;color:var(--muted);cursor:pointer;border-radius:5px;font-size:13px;display:flex;align-items:center;justify-content:center;transition:all .15s;}
   .panel-icon-btn:hover{background:rgba(255,255,255,.08);color:var(--text);}

static/workspace.js

@@ -59,9 +59,32 @@ async function loadDir(path){
         clearPreview();
       }
     }
+    // Fetch git info for workspace root (non-blocking)
+    if(!path||path==='.') _refreshGitBadge();
   }catch(e){console.warn('loadDir',e);}
 }
 
+async function _refreshGitBadge(){
+  const badge=$('gitBadge');
+  if(!badge||!S.session)return;
+  try{
+    const data=await api(`/api/git-info?session_id=${encodeURIComponent(S.session.session_id)}`);
+    if(data.git&&data.git.is_git){
+      const g=data.git;
+      let text=g.branch||'git';
+      if(g.dirty>0) text+=` \u00b7 ${g.dirty}\u2206`; // middot + delta
+      if(g.behind>0) text+=` \u2193${g.behind}`;
+      if(g.ahead>0) text+=` \u2191${g.ahead}`;
+      badge.textContent=text;
+      badge.className='git-badge'+(g.dirty>0?' dirty':'');
+      badge.style.display='';
+    } else {
+      badge.style.display='none';
+      badge.textContent='';
+    }
+  }catch(e){badge.style.display='none';}
+}
+
 function navigateUp(){
   if(!S.session||S.currentDir==='.')return;
   const parts=S.currentDir.split('/');