feat(core): tiered bot management

[Rushaway]

This PR introduces a dynamic tier system to the FakeClients plugin, allowing the number of fake clients (bots) to adjust automatically based on the current number of real players on the server.

Changes:

• Added support for tiered bot limits configured via fakeclients_tiers.cfg.
• Implemented logic to load and sort tier thresholds and max bot counts.
• Adjusted bot spawning and kicking behavior to respect tier limits.
• Added ConVar sm_fakeclients_tiers to enable or disable the tier system.
• Improved bot join timing with staggered timers and random delays for realism.
• Improved SourceTV detection logic
• Change disconnect reason like real client

Benefits:

• More realistic server population management.
• Flexible configuration to suit different server sizes and player counts.
• Prevents server overload by respecting max client slots and reserved slots.
• Easy to enable or disable tier system without changing plugin code.

This update improves the overall player experience by maintaining balanced bot counts dynamically and efficiently.

[Copilot]

Pull request overview

Adds a tier-based fake client (bot) management system to the FakeClients SourceMod plugin so bot counts automatically scale with the current real-player population, driven by a KeyValues config file.

Changes:

• Introduces tier parsing/sorting and tier-driven target bot calculation with reserved-slot awareness.
• Updates bot add/kick logic to use staggered timers with jitter and improved SourceTV detection.
• Adds documentation (README) and a default fakeclients_tiers.cfg configuration.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
README.md	Documents the new tier system, configuration, and ConVars.
addons/sourcemod/scripting/FakeClients.sp	Implements tier loading, dynamic target computation, and staggered bot add/kick behavior.
addons/sourcemod/configs/fakeclients_tiers.cfg	Provides default tier thresholds → max-bot limits.