fix MCP path resolution (addresses #10), CDP connection limit, Playwright signature

[staylor]

What & why

Three small unrelated factual corrections to SKILL.md, grouped because they're all docs-only one-liners.

1. MCP path resolution (addresses point 2 of #10)

The current MCP setup snippets hard-code $HOME/.local/bin/lightpanda, which has two problems:

• Bash form: ignores macOS where the binary may not live in ~/.local/bin.
• JSON form: $HOME doesn't expand inside JSON config strings — this is the second bullet in greenrd's issue Fix Claude Code plugin #10.

Fix:

• Bash form (Claude Code CLI): "$(command -v lightpanda)" resolves the absolute path at install time, regardless of where the binary lives. A one-line comment reminds users to install Lightpanda first (the Install section above MCP setup).
• JSON form: a literal /absolute/path/to/lightpanda placeholder with explicit instruction to fill it in via command -v lightpanda after install. No per-OS path examples (those would presuppose the install method, which varies).

This does not close #10 — only the second bullet. Point 1 ("the skills field is supposed to point to a parent directory of a directory containing a SKILL.md file") is about .claude-plugin/marketplace.json, which this PR doesn't touch.

2. CDP connection limit is now 16, not 1

The Important Notes bullet currently says:

CDP connection limits: Only 1 CDP connection per process.

This hasn't been true for a while — current Lightpanda defaults to 16 simultaneous connections per process and exposes --cdp-max-connections N to tune it. Updates the bullet text and adds the flag to the lightpanda serve options list.

3. Playwright connectOverCDP snippet uses the canonical signature

Both Playwright overloads (connectOverCDP(endpointURL) and connectOverCDP({ endpointURL })) are valid and both work in playwright-core@1.58. The current example uses the object form. Switching to the string form matches what Playwright's own JSDoc Usage examples and published API docs lead with.

This one is a style preference, not a bug. Happy to drop it if you'd prefer the object form, or split it into its own PR.

Verified

• lightpanda serve --cdp-max-connections 32 --port 9222 accepted by current Lightpanda binary.
• chromium.connectOverCDP('ws://127.0.0.1:9222') works under playwright-core@1.58.2.
• command -v lightpanda resolves to brew's /opt/homebrew/bin/lightpanda on Apple Silicon (verified directly). The Linux path is the install script's deterministic install location (~/.local/bin/lightpanda by default, override via LIGHTPANDA_DIR) — verified by construction, not direct execution.

Stack

Independent of #11 (install.sh fixes) and #13 (--block-private-networks defaults) — all three branch off main directly and can be reviewed/merged in any order.

[krichprollsch]

I tried to address point 1. into #15 but I agree your PR is better regarding that.
Can you rebase it please?