Fix command usage message ignoring color tags

[mvanhorn]

Description

Fixes #8616. When a Skript command defines a usage: value with color tags (e.g. <red>Test), the "incorrect usage" message shown to players runs through CommandSender.sendMessage(String), which does not parse Skript's Adventure-style tags. The cooldown-message path at ScriptCommand.java:296 already converts to a Component via TextComponentParser, so colors render correctly there.

Reproduction (from the issue):

command test <integer>:
    usage: <red>Test
    cooldown: 10 seconds
    cooldown message: <red>Test &aTest
    trigger:
        broadcast arg-1

/test foo (wrong arg type) prints the literal <red>Test. /test 1 then immediately again shows the cooldown message in red as expected.

Change

• CommandUsage.getUsageComponent(Event) — new method that resolves the usage VariableString and runs the result through TextComponentParser.instance().parseSafe(...), returning an Adventure Component.
• ScriptCommand.java:340 — use usage.getUsageComponent(event) so sender.sendMessage(...) takes the Adventure overload that honors <red> and &c tags.

bukkitCommand.setUsage(usage.getUsage()) (line 245) is left unchanged: Bukkit's PluginCommand.setUsage takes a plain String and is wired into the Bukkit registry, not into our send-to-player path.

The help-topic output at line 378 (ChatColor.GOLD + "Usage" + ChatColor.RESET + ": " + usage.getUsage()) is intentionally out of scope. It mixes Bukkit ChatColor legacy codes with the usage string and would require a separate Component-prefix refactor; the user's report was specifically about the invalid-argument feedback path.

Validation

• ./gradlew compileJava ✅
• ./gradlew compileTestJava ✅
• Type-check confirms sender.sendMessage(Component) resolves on Paper / Bukkit's Adventure-aware CommandSender.

The runtime color render itself can only be exercised on a Minecraft server, which is what Skript's .sk test harness already does for the cooldown path. Happy to add a runtime .sk regression for usage: if reviewers prefer.

AI assistance disclosure

Per .github/CONTRIBUTING.md, disclosing AI assistance:

This PR was written with assistance from Claude (Anthropic). The bug analysis (cooldown vs. usage code paths in ScriptCommand) and the patch were reviewed before submission.

Fixes #8616

[mvanhorn]

Switched to parse() in 156b2b0 per @ShaneBeee and @sovdeeth -- since command usage is 100% Skripter-controlled and unsafe tags can't otherwise be used in the entry, the safe-only restriction was over-tight. Updated the Javadoc to document why unsafe parsing is appropriate here. Verified locally with ./gradlew compileJava (BUILD SUCCESSFUL on Java 17).

[APickledWalrus]

You'll need to update this to target dev/patch rather than master (should be able to change at the top)