help: show core plugins in root ‘?’ dynamically; remove ‘Lc’ entry

[DivInstance]

Summary

This PR updates the root ? help in Radare2 to include a dynamic “Core plugins” section and removes the Lc entry. Users can now discover core plugin commands directly from the main help without relying on Lc.

Changes:

• Modified libr/core/cmd_help.inc.c :
  • Removed Lc line from help_msg_root.
  • In cmd_help() for root ?, added a dynamic help block built from core->rcmd->plist :
    • Header: “Core plugins:”
    • Per plugin: [ ? ]

Rationale:

• Listing core plugins directly in root help improves discoverability and keeps help consistent with the loaded plugin set.
• Avoids duplicating a static Lc entry when the plugin list is readily available programmatically.

Testing:

• Build: ./configure && make -j
• Lint: sys/lint.sh

Impact:

• Help output improvement only; no behavioral changes to command execution.
• Deprecates the Lc row in root ? in favor of the inline dynamic list.

Resolves #23724

[trufae]

the way to make core plugins visible shpuld be listing their help in the root help instead of exposing Lc in here imho. But we must find a fast way to make the commands created by core plugins available in their subcommands helps and thats the current blocker imho

[DivInstance]

I agree with the direction. Instead of exposing Lc, I’ll surface core plugin help in the root ? and in the corresponding subcommand helps.

[trufae]

the code assumes the plugin name is aligned with the commands provided in the plugin, which is not always correct. we probably need a way for core plugins to expose a help message or list of commands provided instead of relying on the name. also ideally those commands shuold be listed in the right help message. but the concern for this would be about performance when doing "?*"

[trufae]

just r_list_length() no need to iterate

[trufae]

move all this into a separate function