[FEATURE] Sort slash commands by usage frequency in session

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Currently, slash commands in the autocomplete menu are sorted alphabetically. When working in a session, users repeatedly use the same subset of commands (e.g. /compact, /clear, /review). Having to scroll through or type more characters to find frequently-used commands adds friction, especially for power users with many custom skills and plugins installed.

Proposed Solution

Track command invocation frequency within a session and surface the most-used commands at the top of the slash command autocomplete list.

Ideally:

• Most-used commands float to the top during the current session
• - Optionally persist frequency data across sessions (configurable)
• - - Fuzzy search still works as today on top of frequency-sorted list
• - - - Could be exposed as a hook or config option so power users can control it without requiring a bundle patch

Alternative Solutions

Patching the Claude Code bundle directly to replace alphabetical sort with frequency-based logic. Works but breaks on every update. No official hook or config option exists today to control slash command ordering.

Priority

High - Significant impact on productivity

Feature Category

CLI commands and flags

Use Case Example

I have 30+ custom skills and OMC plugin commands installed. In a typical session I use /compact, /clear, and 2-3 project-specific skills repeatedly. Currently I type "/" and have to scroll past many alphabetically-sorted commands or type several characters to filter. If the most-used commands surfaced at the top automatically, the workflow would be significantly faster.

Additional Context

_No response_