feat: add message_click_actions tui config

[macknight]

Issue for this PR

Closes #N/A

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

Adds a new message_click_actions boolean option to TUI config (tui.json) that allows users to disable the message action popup (Revert/Copy/Fork) that appears when clicking on user messages in the chat session.

Some users have a habit of clicking around in the terminal, which accidentally triggers the popup frequently. This option gives users control over this behavior.

Changes:

• packages/opencode/src/cli/cmd/tui/config/tui-schema.ts: Added message_click_actions: z.boolean().optional() to TuiOptions, described as "Enable or disable the message click action popup (Revert/Copy/Fork). Default: true"
• packages/opencode/src/cli/cmd/tui/routes/session/index.tsx: Added guard if (tuiConfig.message_click_actions === false) return in the onMouseUp handler before showing the action dialog

Usage in ~/.config/opencode/tui.json:

{
  "message_click_actions": false
}

Default behavior is unchanged (popup shown when option is not set or set to true).

How did you verify your code works?

The change is minimal — follows the exact same pattern as existing boolean TUI options (e.g., mouse config in the same schema consumed in app.tsx). The guard condition mirrors existing early-return patterns in the same file.

Screenshots / recordings

N/A — no UI change, only a config option that suppresses existing behavior.

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR

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