feat(daemon): add configurable daemon endpoint

[yunhungo]

Description

This PR adds configurable daemon host/port support for the CLI daemon and browser extension.

Changes included:

• Add persistent daemon config via ~/.opencli/daemon.yaml
• Support configuring daemon host and port from CLI commands
• Keep environment variable overrides for daemon endpoint settings
• Update daemon client/status/doctor output to reflect the active endpoint
• Add browser extension support for connecting to a specific daemon host/port
• Add popup UI for editing extension daemon host/port and refresh status after saving
• Update docs for daemon/browser bridge configuration

Related issue:

Type of Change

• 🐛 Bug fix
• ✨ New feature
• 🌐 New site adapter
• 📝 Documentation
• ♻️ Refactor
• 🔧 CI / build / tooling

Checklist

• I ran the checks relevant to this PR
• I updated tests or docs if needed
• I included output or screenshots when useful

Documentation (if adding/modifying an adapter)

• Added doc page under docs/adapters/ (if new adapter)
• Updated docs/adapters/index.md table (if new adapter)
• Updated sidebar in docs/.vitepress/config.mts (if new adapter)
• Updated README.md / README.zh-CN.md when command discoverability changed
• Used positional args for the command's primary subject unless a named flag is clearly better
• Normalized expected adapter failures to CliError subclasses instead of raw Error

Screenshots / Output

Relevant checks run:

bun run test -- src/daemon-config.test.ts src/browser/daemon-client.test.ts src/commands/daemon.test.ts