docs(stub): make the Pages stub and package metadata agent-agnostic

Bring the GitHub Pages stub in line with the reworked README: drop
"Claude Code skills" from the title, name all four harnesses (OpenCode
was missing entirely), and lead with the "Playwright for coding agents"
tagline in both the meta description and the visible lead paragraph.
The old lead also read "agents and their Claude Code skills", which
parsed wrong even for a Claude-only framing.

The stub's own comment says its description mirrors the package
metadata, so pyproject's description and keywords gain OpenCode too —
otherwise that comment stops being true the moment the stub changes.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016v9L8gXbq4MzH6V9JZPqcb

Author: uipreliga

.github/pages-stub/index.html

@@ -3,7 +3,7 @@
   <head>
     <meta charset="utf-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1" />
-    <title>Coder Eval — evaluate AI coding agents and Claude Code skills</title>
+    <title>Coder Eval — evaluate AI coding agents and their skills</title>
     <!--
       The description is here for link previews and for anyone reading source,
       not for ranking: this page is noindex (see below), so search engines will
@@ -12,7 +12,7 @@
     -->
     <meta
       name="description"
-      content="Coder Eval is an open-source framework for evaluating and benchmarking AI coding agents and Claude Code skills — sandboxed runs of Claude Code, Codex, and Gemini against declarative YAML tasks, with weighted scoring and CI gates. Documentation: coder-eval.com/docs"
+      content="Coder Eval is Playwright for coding agents: an open-source, agent-agnostic framework for evaluating and benchmarking AI coding agents and their skills — sandboxed runs of Claude Code, Codex, Antigravity (Gemini), or OpenCode against declarative YAML tasks, with weighted scoring and CI gates. Documentation: coder-eval.com/docs"
     />
 
     <!--
@@ -225,9 +225,10 @@
       -->
       <h1 class="sr-only">Coder Eval</h1>
       <p class="lead">
-        An open-source framework for evaluating and benchmarking AI coding agents and their Claude
-        Code skills: it runs a real agent — Claude Code, Codex, or Gemini — in a sandbox against
-        declarative YAML tasks, then scores the files and commands the agent actually produced.
+        <strong>Playwright for coding agents.</strong> An open-source, agent-agnostic framework for
+        evaluating and benchmarking AI coding agents and their skills: it runs a real agent — Claude
+        Code, Codex, Antigravity (Gemini), or OpenCode — in a sandbox against declarative YAML
+        tasks, then scores the files and commands the agent actually produced.
       </p>
       <p class="notice">
         The documentation has moved to

pyproject.toml

@@ -1,15 +1,15 @@
 [project]
 name = "coder-eval"
 version = "0.11.6"
-description = "Evaluate, benchmark, and A/B-test AI coding agents (Claude Code, Codex, Gemini/Antigravity) with sandboxed, reproducible YAML task suites."
+description = "Evaluate, benchmark, and A/B-test AI coding agents (Claude Code, Codex, Gemini/Antigravity, OpenCode) with sandboxed, reproducible YAML task suites."
 readme = "README.md"
 license = "Apache-2.0"
 requires-python = ">=3.13"
 authors = [{ name = "UiPath", email = "coder-eval@uipath.com" }]
 keywords = [
     "ai", "llm", "agent", "coding-agent", "evaluation", "eval", "evals",
     "benchmark", "swe-bench", "claude", "claude-code", "codex", "anthropic",
-    "gemini", "antigravity", "sandbox", "code-generation", "agent-evaluation",
+    "gemini", "antigravity", "opencode", "sandbox", "code-generation", "agent-evaluation",
     "llm-evaluation", "llm-eval", "ai-evaluation", "skills-evaluation",
     "claude-skills", "claude-code-skills", "agent-skills", "skillsbench",
     "agent-testing", "llmops",