feat: slash command parity + skill autocomplete — v0.50.91 (PR #711)

Combines PR #618 (@renheqiang) slash command parity (/retry /undo /stop /title /status /voice) with PR #701 (@franksong2702) skill autocomplete. 1469 tests pass. Closes #460.

Co-authored-by: renheqiang <renheqiang@users.noreply.github.com>
Co-authored-by: franksong2702 <franksong2702@users.noreply.github.com>

tests/test_sprint47.py

@@ -0,0 +1,39 @@
+"""
+Sprint 47 tests: skill-backed slash commands appear in the Web UI autocomplete.
+
+Covers:
+- commands.js lazily loads /api/skills for slash autocomplete
+- built-in commands still win over skill name collisions
+- boot.js primes the async skill load when typing '/'
+- the dropdown marks skill-backed entries visually
+"""
+import pathlib
+
+
+REPO_ROOT = pathlib.Path(__file__).parent.parent
+COMMANDS_JS = (REPO_ROOT / "static" / "commands.js").read_text(encoding="utf-8")
+BOOT_JS = (REPO_ROOT / "static" / "boot.js").read_text(encoding="utf-8")
+STYLE_CSS = (REPO_ROOT / "static" / "style.css").read_text(encoding="utf-8")
+
+
+def test_skill_commands_are_loaded_from_api_skills_for_autocomplete():
+    assert "loadSkillCommands" in COMMANDS_JS
+    assert "api('/api/skills')" in COMMANDS_JS
+    assert "source:'skill'" in COMMANDS_JS
+
+
+def test_builtin_commands_take_precedence_over_skill_slug_collisions():
+    # In the combined implementation, REGISTRY (agent registry + WEBUI_ONLY) wins over skills
+    assert ("if(COMMANDS.some(c=>c.name===slug)) return null;" in COMMANDS_JS or
+            "if(REGISTRY.some(c=>c.name===slug)) return null;" in COMMANDS_JS), \
+        "Built-in commands must block skill slug collisions"
+
+
+def test_typing_slash_primes_async_skill_command_loading():
+    assert "ensureSkillCommandsLoadedForAutocomplete" in BOOT_JS
+    assert "ensureSkillCommandsLoadedForAutocomplete();" in BOOT_JS
+
+
+def test_dropdown_has_visual_badge_for_skill_backed_entries():
+    assert "cmd-item-badge-skill" in STYLE_CSS
+    assert "slash_skill_badge" in COMMANDS_JS