docs: add performance api docs

Author: Jake Champion

documentation/docs/globals/performance/now.mdx

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+---
+hide_title: false
+hide_table_of_contents: false
+pagination_next: null
+pagination_prev: null
+---
+
+# performance.now()
+
+The **`performance.now()`** method returns a high resolution timestamp in milliseconds.
+It represents the time elapsed since [`performance.timeOrigin`](./timeOrigin.mdx) (the time when the worker was instantiated).
+
+## Syntax
+
+```js
+now()
+```
+
+### Parameters
+
+None.
+
+### Return value
+
+Returns a number which represents the time since worker instantation measured in milliseconds.

documentation/docs/globals/performance/timeOrigin.mdx

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+---
+hide_title: false
+hide_table_of_contents: false
+pagination_next: null
+pagination_prev: null
+---
+
+# performance.timeOrigin
+
+The **`timeOrigin`** read-only property of the Performance interface returns the high resolution timestamp that is used as the baseline for performance-related timestamps.
+
+This value represents the time when the worker was instantiated.
+
+### Value
+
+Returns a number which represents the time when the worker was instantation.

documentation/versioned_docs/version-2.3.0/globals/performance/now.mdx

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+---
+hide_title: false
+hide_table_of_contents: false
+pagination_next: null
+pagination_prev: null
+---
+
+# performance.now()
+
+The **`performance.now()`** method returns a high resolution timestamp in milliseconds.
+It represents the time elapsed since [`performance.timeOrigin`](./timeOrigin.mdx) (the time when the worker was instantiated).
+
+## Syntax
+
+```js
+now()
+```
+
+### Parameters
+
+None.
+
+### Return value
+
+Returns a number which represents the time since worker instantation measured in milliseconds.

documentation/versioned_docs/version-2.3.0/globals/performance/timeOrigin.mdx

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+---
+hide_title: false
+hide_table_of_contents: false
+pagination_next: null
+pagination_prev: null
+---
+
+# performance.timeOrigin
+
+The **`timeOrigin`** read-only property of the Performance interface returns the high resolution timestamp that is used as the baseline for performance-related timestamps.
+
+This value represents the time when the worker was instantiated.
+
+### Value
+
+Returns a number which represents the time when the worker was instantation.