v0.3.0

Changes

• Warm-cache sessions only at start-up. When the plugin starts or reloads, it times sessions that are already waiting from the end of their last turn. A session idle for less than the idle delay is prepared when that delay runs out. Sessions idle longer have an expired provider cache, so they are skipped: no preparation and no tokens. They qualify again after their next turn.
• Authenticated page endpoints. The page now talks to /api/idle-compact/events and /api/idle-compact/apply on DSH's /api channel, behind DSH's login and same-origin checks. The old routes had no authentication.
• DSH components. The settings form and the Apply button use @deepseek-ai/dsh-client-ui-primitives.
• Code split into src/ modules, with constants in one place.
• Test suite (npm test): 226 Host tests per DSH runtime (0.2.1-alpha.3, 0.2.1-rc.2) and 51 client tests.