feat(v0.6): show CLAUDE.md on the project detail page + /init generate/update button

The detail page now reads <repo>/CLAUDE.md and shows it in a scrollable
monospace box, with one smart button: "↻ Update" when it exists / "✨ Generate"
when it doesn't. The button opens an interactive Claude session in the repo
running /init (claude "/init") so you review what it writes — reuses the project
launcher, no new backend orchestration, stays a byte-shuttle.

- ProjectDetail += hasClaudeMd / claudeMd; buildProjectDetail reads CLAUDE.md
  (truncated 64KB, best-effort, in the existing Promise.all)
- renderProjectDetail: CLAUDE.md section (content box or empty state) + button
- style.css: .proj-section-row / .proj-claudemd-btn / .proj-claudemd

Tests +5 (458): backend read present/absent; frontend content+Update,
empty+Generate, button opens `claude "/init"`. Verified: tsc clean, full suite
green, build OK, curl returns the content, in-browser shows the box + button.

test/projects.test.ts

@@ -398,6 +398,23 @@ describe('buildProjectDetail', () => {
     expect(d!.sessions.map((s) => s.id).sort()).toEqual(['a', 'b'])
   })
 
+  it('includes CLAUDE.md content when present', async () => {
+    const dir = path.join(tmp, 'withmd')
+    await fs.mkdir(dir)
+    await fs.writeFile(path.join(dir, 'CLAUDE.md'), '# Project\nbe excellent')
+    const d = await buildProjectDetail(makeCfg({}), dir, [])
+    expect(d!.hasClaudeMd).toBe(true)
+    expect(d!.claudeMd).toContain('be excellent')
+  })
+
+  it('reports no CLAUDE.md when absent', async () => {
+    const dir = path.join(tmp, 'nomd')
+    await fs.mkdir(dir)
+    const d = await buildProjectDetail(makeCfg({}), dir, [])
+    expect(d!.hasClaudeMd).toBe(false)
+    expect(d!.claudeMd).toBeUndefined()
+  })
+
   it('lists worktrees for a real git repo (gated on git)', async () => {
     if (!(await gitAvailable())) return
     await fs.mkdir(path.join(tmp, 'realrepo'))