Enhance GM commands configuration with per-account overrides and default settings (#6)

TLDR: Introduce per-account configurations for GM commands, allowing custom GM levels and command lists, along with default settings for accounts without specific overrides. Setting a GM Level (at least 1) is important to make some features to work - such as the keeping the player extra flags permanent after the relog (e.g. gm on/visible flags)

This pull request introduces a major refactor and extension of the GM commands configuration system. The changes provide more granular control over which accounts can use GM commands, their permission levels, and the commands available to them. The configuration file now supports per-account overrides, default levels, and command lists, while the codebase is updated to support these new features with a more robust and flexible structure.

Configuration enhancements:

* Added support for specifying a default GM level (`GmCommandsModule.DefaultLevel`) and a default allowed command list (`GmCommandsModule.DefaultCommands`) in `conf/mod_gm_commands.conf.dist`. These apply to all managed accounts unless overridden per account. Per-account overrides for both level and allowed commands are now supported.

Codebase refactor and feature additions:

* Replaced the old `LoadAccountIds` and `LoadAllowedCommands` methods with a single `Reload` method in `GMCommands`, reflecting the new configuration structure.
* Introduced per-account configuration via the `AccountConfiguration` struct, supporting optional GM level and allowed command set for each account.
* Added logic to normalize and validate command names and account levels, as well as improved error handling for invalid account IDs.
* Enhanced command permission checking: `IsCommandAllowed` now considers both the account ID and the specific command, supporting per-account and default command lists.
* Added methods to associate command metadata and handler information, enabling more detailed permission and command tracking.

Author: Yehonal

.github/README.md

@@ -0,0 +1,79 @@
+# GM Commands Module
+
+This module lets you curate the set of chat commands that selected accounts can use without granting them the full GM security level. It hooks into the AzerothCore command system to hide or block commands that are not explicitly whitelisted, while still enforcing the regular command security for every other player.
+
+## Capabilities
+- Manage a list of account IDs controlled by the module.
+- Assign a shared default GM level and default command list for those accounts.
+- Override the GM level or allowed commands per account.
+- Allow commands that normally require a higher security level when they are explicitly whitelisted.
+- Always allow commands that require security level `SEC_PLAYER` (0).
+
+## Configuration Files
+The module looks for its configuration in both `modules/mod_gm_commands.conf.dist` and `modules/mod_gm_commands.conf` inside your server configuration directory (for example `env/dist/etc/modules/`).
+
+When the server starts (or the config is reloaded), the module reads `.conf.dist` first and then `.conf`. Keys present in the non-`.dist` file override the defaults. This allows you to keep personal changes out of version control while still benefiting from distribution updates.
+
+### Required Keys
+- `GmCommandsModule.Enable`: Set to `1` to activate the module.
+- `GmCommandsModule.AccountIds`: Comma-separated list of account IDs that the module manages. Only accounts in this list are affected.
+
+### Optional Defaults
+- `GmCommandsModule.DefaultLevel`: GM level applied to managed accounts that do not define their own level. Clamped between `SEC_PLAYER (0)` and `SEC_ADMINISTRATOR (3)`.
+- `GmCommandsModule.DefaultCommands`: Comma-separated list of commands granted to managed accounts that do not define their own command list. Commands that require level 0 are still automatically available even if they are not listed.
+
+### Per-Account Overrides
+Use the following keys to override defaults for a specific account, replacing `<AccountId>` with the numeric ID:
+- `GmCommandsModule.Account.<AccountId>.Level`
+- `GmCommandsModule.Account.<AccountId>.Commands`
+
+Both files (`mod_gm_commands.conf.dist` and `mod_gm_commands.conf`) are scanned, so you may define an override in either place. Values found in the non-`.dist` file take precedence.
+
+#### Command List Formatting
+Commands are stored in a normalized, lowercase form:
+- Trim spaces around each entry.
+- Collapse multiple inner spaces to a single space.
+- Use the full chat command path. For example, the command shown in chat as `.character level` must be written as `character level`; `levelup` can be listed as-is because it is a top-level command.
+
+You can list multi-word commands exactly as they appear after the leading dot, separated by commas:
+```
+GmCommandsModule.Account.3.Commands = "character level, character rename, levelup, gm visible"
+```
+
+## Runtime Behaviour
+- When a GM account uses a command, the module records the command name and its required security level.
+- If an account is in the managed list and the command requires more than `SEC_PLAYER`, the module checks the whitelist before the core performs its visibility/security check.
+- Whitelisted commands return early from the visibility hook, effectively bypassing the security-level requirement for that account. Non-whitelisted commands continue through the normal core checks and are blocked with “You are not allowed to use this command.”
+- The module logs the resolved default settings and per-account overrides at startup (log channel `modules.gmcommands`) to aid troubleshooting.
+
+## Reloading Configuration
+After editing the configuration, either restart the worldserver or run `.reload config` from a GM account with adequate privileges. The module will re-read both configuration files and log the updated account summaries.
+
+## Troubleshooting
+- Ensure the account ID is listed in `GmCommandsModule.AccountIds`; otherwise the account is ignored.
+- Use the full command name (including subcommand structure) in the whitelist. If a command still reports “does not exist,” verify the spelling and normalization.
+- Check the worldserver log for `modules.gmcommands` entries to confirm that the module picked up your overrides.
+- Commands that require only `SEC_PLAYER` never need to be listed; if users cannot run them, the issue lies elsewhere (permissions, syntax, etc.).
+
+## Example
+```
+GmCommandsModule.Enable = 1
+GmCommandsModule.AccountIds = "3,4"
+GmCommandsModule.DefaultLevel = 0
+GmCommandsModule.DefaultCommands = "go"
+
+GmCommandsModule.Account.3.Level = 1
+GmCommandsModule.Account.3.Commands = "character level, levelup, gm, gm visible"
+
+GmCommandsModule.Account.4.Commands = "appeal, go, ticket"
+```
+
+In this example account 3 keeps security level 1 but can run `character level` and `levelup`, while account 4 inherits the default security level (0) yet receives a custom command list.
+
+## Development Notes
+The implementation lives in `src/GmCommands.cpp` and exposes a singleton (`sGMCommands`) responsible for:
+- Loading overrides from `sConfigMgr` and the module config files.
+- Normalizing command names and caching per-command required security.
+- Hooking `AllCommandScript` to hide or allow commands based on the configured whitelist.
+
+Any changes to the command registry should keep the normalization logic in mind so that configuration values remain compatible.

README.md

@@ -18,17 +18,41 @@ GmCommandsModule.Enable = 1
 
 #
 #    GmCommandsModule.AccountIds
-#        Description: Allow the specified accounts to use commands. Separated by comma
-#
+#        Description: Comma separated list of account identifiers that should be managed by this module.
+#                     Each listed account can optionally define a custom GM level or custom command list.
 #
 
 GmCommandsModule.AccountIds = ""
 
 #
+#    GmCommandsModule.DefaultLevel
+#        Description: Default GM level assigned to managed accounts that do not define their own level.
+#                     The value is clamped between SEC_PLAYER (0) and SEC_ADMINISTRATOR (3).
+#        Default:     0 - SEC_PLAYER
 #
-#    GmCommandsModule.AllowedCommands
-#        Description: Allow the specified commands to be used. Separated by comma.
+
+GmCommandsModule.DefaultLevel = 0
+
 #
+#    GmCommandsModule.DefaultCommands
+#        Description: Default comma separated list of commands (case-insensitive) allowed to managed accounts
+#                     when a specific command list is not defined for the account. Commands that require
+#                     security level 0 are always allowed.
+#        Default:     ""
 #
 
-GmCommandsModule.AllowedCommands = ""
+GmCommandsModule.DefaultCommands = ""
+
+#
+# Per-account overrides
+#
+#    GmCommandsModule.Account.<AccountId>.Level
+#        Description: Override the GM level for the specified account id.
+#                     Omit this entry to use `GmCommandsModule.DefaultLevel`.
+#        Example:     GmCommandsModule.Account.42.Level = 2
+#
+#    GmCommandsModule.Account.<AccountId>.Commands
+#        Description: Override the allowed commands for the specified account id. Provide a comma
+#                     separated, case-insensitive list. Leave unset to inherit `GmCommandsModule.DefaultCommands`.
+#        Example:     GmCommandsModule.Account.42.Commands = "gm, gm visible, account"
+#