refactor: migrate to Zig 0.16.0-dev.2676 PriorityQueue API

[GrapeBaBa]

• Rename PriorityQueue methods: init→initContext, add→push, remove→pop, removeIndex→popIndex, deinit now takes allocator
• Add self.* = undefined in EventClock.deinit for memory poisoning
• Split triple compound condition in SlotClock AdvanceIterator
• Update workaround comments for macOS GCD bug #31307

[Copilot]

Pull request overview

Migrates the clock/event loop implementation to Zig 0.16.0-dev.2676 by updating std.PriorityQueue usage and related cleanup, while also improving some internal safety/clarity in deinit paths and iterator logic.

Changes:

• Updated std.PriorityQueue usage in EventClock to the new API (initContext, push, pop, popIndex, deinit(allocator)).
• Added memory poisoning in EventClock.deinit (self.* = undefined) after releasing resources.
• Refactored SlotClock.AdvanceIterator epoch-boundary condition into clearer nested optionals and refreshed macOS GCD workaround comments/tests.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
src/SlotClock.zig	Refactors epoch-boundary detection in AdvanceIterator to avoid triple-compound optional checks.
src/EventClock.zig	Migrates waiter priority queue calls to Zig 0.16 API; adjusts deinit, comments, and a real-time test name.

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[Copilot]

std.Io.sleep errors are being swallowed silently here. If sleep starts failing persistently (e.g., due to an I/O subsystem issue), the loop will tight-spin and provide no diagnostic signal. Consider capturing the error (catch |err|) and either logging it (ideally rate-limited) and/or stopping the loop on non-transient errors to avoid high CPU usage and invisible failures.

Suggested change

	) catch {
	// Transient error — re-check stopped flag.
	continue;
	) catch |err| {
	std.log.err("EventClock: std.Io.sleep failed: {s}; stopping auto loop to avoid spin", .{@errorName(err)});
	self.stop();
	break;