init at work

typescript/bits/20-alignedstarts-concept.md

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+# Understanding `alignedStarts`
+
+`alignedStarts` is an array of date boundaries that match your backend schedule rule.
+
+## Concept
+
+```ts
+const alignedStarts: Date[] = [];
+```
+
+Each item is a valid period boundary (for example Monday 00:00 in backend-local schedule terms).
+
+Later, you form intervals by pairing adjacent items:
+
+```ts
+const start = alignedStarts[index];
+const end = alignedStarts[index + 1];
+```
+
+So if `alignedStarts` has `N` items, you can make up to `N-1` intervals.
+
+## Why this is useful
+
+- Keeps schedule boundaries consistent.
+- Makes interval generation deterministic.
+- Handles DST-safe boundaries when generated correctly.