feat: allow other plugins to start any helper via PluginMessage

[ajkatz]

Quest Helper already participates in the RuneLite PluginMessage ecosystem outbound — it posts to shortestpath (DetailedQuestStep) and notenoughrunes (QuestRequirementsPanel) — but has no inbound receiver, so other plugins can't deep-link into it. This adds the other direction using the same convention:

field	value
namespace	questhelper
name	start
data	{ "quest": "<helper display name>", "source": "<requesting plugin display name>" } — both required

eventBus.post(new PluginMessage("questhelper", "start",
    Map.of("quest", "Dragon Slayer I", "source", "<My Plugin>")));
eventBus.post(new PluginMessage("questhelper", "start",
    Map.of("quest", "Ardougne Elite Diary", "source", "<My Plugin>")));
eventBus.post(new PluginMessage("questhelper", "start",
    Map.of("quest", "Herb run", "source", "<My Plugin>")));      // generic helper
eventBus.post(new PluginMessage("questhelper", "start",
    Map.of("quest", "Agility", "source", "<My Plugin>")));       // skill helper

The start is announced in the player's chat — Quest Helper for Dragon Slayer I started, requested by My Plugin. — so it's always visible which plugin triggered it. Messages without a source are ignored.

Works for every helper type, not just quests: the handler delegates to the existing QuestMenuHandler#startUpQuest(String) — the same generic path the quest list and onChatMessage auto-start use — so quests, miniquests, achievement diaries, skill helpers, generic helpers, and player-made quests all resolve through QuestHelperQuest.getByName, and the Shield of Arrav / RFD special cases are inherited rather than duplicated. The call is wrapped in clientThread.invokeLater since PluginMessage arrives on the poster's thread and the Shield of Arrav branch reads the local player.

Malformed or foreign messages are ignored (namespace/name gate + payload type checks), so nothing changes for anyone who doesn't post the message.

Motivation: I maintain the Goal Planner hub plugin and want "resume in Quest Helper" on quest and diary goals — but this is deliberately generic so any plugin (or future Quest Helper features) can use it. Tested end-to-end: a dev client running both plugins, with Goal Planner posting the message and this handler starting quest and diary helpers.

./gradlew build green.

🤖 Generated with Claude Code

[pajlada]

The snapshot build failures are fine, they're an issue on our end not yours

[ajkatz]

The snapshot build failures are fine, they're an issue on our end not yours

thank you for the quick feedback! I'll wait until those are fixed

[ajkatz]

@pajlada rebased this and looks like it's no longer hitting that build issue now 🥳