Docs: Document System Keyboard & Click Modifier Flags (.ctrl, .alt, .shift, .meta, .cmd) in Action Event Handlers

[nathanschmid08]

Summary

Document system key modifier flags (.ctrl, .alt, .shift, .meta, .cmd) supported in template event bindings (e.g. @click.ctrl="openInNewTab", @keydown.meta.enter="submitForm").

Context & Current State

EventBinder supports system modifier key filters via SYSTEM_MODIFIER_MAP (ctrl, alt, shift, meta, cmd). While key modifiers like .enter and .esc are documented in events.md, system key modifier flags and combination syntax (such as @keydown.cmd.enter) are omitted from the event modifiers reference table and usage guides.

Proposed Documentation Changes

1. Actions & Event Handling (docs/src/content/docs/core-concepts/events.md):
   • Update the Event Modifiers table to include .ctrl, .alt, .shift, .meta, and .cmd with descriptions of their behavior on mouse and keyboard events.
   • Add practical code examples showing system modifier bindings (e.g. @click.ctrl, @click.meta, @keydown.cmd.enter).
   • Clarify platform differences (e.g. .cmd as a cross-platform alias for .meta) and explain how system modifier key evaluation runs before event expression execution.

Labels

• documentation
• enhancement
• good first issue