refactor: move g_ApplicationRunning global to Application static member (P2_16)

[Cle2ment]

Batch 10 Peanut static globals to member variables

[Cle2ment]

/oc check pr problems

[opencode-agent]

PR #21 (P2-16) — 2 problems found:

1. AGENTS.md stale — Batch 10 row (line 270) still shows ⬚ deferred and the REMAINING table P2-16 (line 282) is unmarked. The merge was successful but the knowledge base wasn't updated per the update rule.

2. AGENTS.md header outdated — Line 3-4 still references commit 5b97357 (now c506c3f) and says "Batch 1-8 complete" (should be "Batch 1-10 complete").

No code issues. The implementation is clean: g_ApplicationRunning → Application::s_IsRunning (private static member + public IsRunning() accessor) in Peanut submodule. 3 files changed, proper encapsulation, zero references left behind. RayTracing application code is unaffected.

opencode session  |  github run