New Feature: Support for ${line} and ${column} placeholders in the command line settings

The Command Line field in the extension settings now supports two new placeholders:
- ${line} for the 1-based line number
- ${column} for the 1-based column number (offset from the beginning of the line)

Example usage:
/usr/local/bin/gvim --nofork +"call cursor(${line}, ${column})"

Notes:
- Quotes (single or double) are expanded similarly to shells.
- Variable expansion (like $VAR) and backslash escaping are not supported.
- Quotes are required when passing arguments that contain spaces. Without quotes, a line like +call cursor(${line}, ${column}) would be split into three arguments: +call, cursor(${line}, and ${column}).

New Feature: Support for ${line} and ${column} placeholders in the command line settings

The Command Line field in the extension settings now supports two new placeholders:
- ${line} for the 1-based line number
- ${column} for the 1-based column number (offset from the beginning of the line)

Example usage:
/usr/local/bin/gvim --nofork +"call cursor(${line}, ${column})"

Notes:
- Quotes (single or double) are expanded similarly to shells.
- Variable expansion (like $VAR) and backslash escaping are not supported.
- Quotes are required when passing arguments that contain spaces. Without quotes, a line like +call cursor(${line}, ${column}) would be split into three arguments: +call, cursor(${line}, and ${column}).

See https://github.com/rosmanov/chrome-bee/issues/12

Fixed Shadow DOM Traversal:
- Fields hidden behind the Shadow DOM are now correctly detected and traversed by the extension's content script.This fix restores the ability to invoke the external editor for Markdown comment editors and search fields on sites like Reddit.

Known Limitations
- Advanced Rich Text Editors: Fields rendered via internal state management (e.g., React-based editors) remain unsupported. Programmatic updates to these fields are still not reflected reliably, as these editors treat external input differently from direct user typing.

Removed host_permissions permission request

Also, performed some internal cleanup.

- Upgraded manifest version to version 3.
- Fixed a bug where editor text might was sent to all tabs instead of the calling tab.

- Extension settings are now stored in the sync storage area
- Translated to Russian

Fixed a bug in extension preferences where extension field and "Remove" buttons were not available.

Added support for custom filename extensions. The new feature works only with recent versions of the host application: either BeeCtl (https://github.com/rosmanov/bee-host) version 1.2.0 or newer, or the host app currently included in the extension repository (https://github.com/rosmanov/chrome-bee).

Note, BeeCtl binaries will be uploaded to SourceForge soon.

Fix: editor was not opened if no extension settings were ever saved.

Added support for a native messaging host written in C ( https://github.com/rosmanov/bee-host )
Fixed text field was not updated when the user switched to another tab
Changed event page is now converted to persistent background page

- Added support for the arguments accepted by a C implementation of the host app: https://github.com/rosmanov/bee-host
- Fixed: multiple editor windows were opened in Redmine