docs: add link to option in explanation

Author: cjw783

docs/src/pages/Demos.mdx

@@ -69,7 +69,7 @@ Made with [@egjs/grid](https://github.com/naver/egjs-grid)
 ## Reactive API demo
 
 ### Pagination
-> You can synchronize Flicking with Pagination using `currentPanelIndex` and `totalPanelCount`.
+> You can synchronize Flicking with Pagination using <Link to={useBaseUrl("docs/api/FlickingReactiveState")}>currentPanelIndex</Link> and <Link to={useBaseUrl("docs/api/FlickingReactiveState")}>totalPanelCount</Link>.
 
 <Columns>
   <ColumnItem is={12} className="is-flex is-flex-direction-column is-align-items-center">
@@ -428,7 +428,7 @@ onMounted(() => {
 </Tabs>
 
 ### Prev / Next Button
-> You can synchronize Flicking with Prev/Next buttons using `isReachStart` and `isReachEnd`.
+> You can synchronize Flicking with Prev/Next buttons using <Link to={useBaseUrl("docs/api/FlickingReactiveState")}>isReachStart</Link> and <Link to={useBaseUrl("docs/api/FlickingReactiveState")}>isReachEnd</Link>.
 
 <Columns>
   <ColumnItem is={12} className="is-flex is-flex-direction-column is-align-items-center">
@@ -744,7 +744,7 @@ onMounted(() => {
 </Tabs>
 
 ### Progress Bar
-> You can synchronize Flicking with Progress Bar using `progress`.
+> You can synchronize Flicking with Progress Bar using <Link to={useBaseUrl("docs/api/FlickingReactiveState")}>progress</Link>.
 
 <Columns>
   <ColumnItem is={12} className="is-flex is-flex-direction-column is-align-items-center">
@@ -976,7 +976,7 @@ onMounted(() => {
 </Tabs>
 
 ### Parallax
-> You can create a Parallax effect for each panel using `indexProgress`.
+> You can create a Parallax effect for each panel using <Link to={useBaseUrl("docs/api/FlickingReactiveState")}>indexProgress</Link>.
 
 <Columns>
   <ColumnItem is={12} className="is-flex is-flex-direction-column is-align-items-center">
@@ -1285,7 +1285,7 @@ onMounted(() => {
 </Tabs>
 
 ### Slide Over
-> You can create a Slide Over effect using `indexProgress`.
+> You can create a Slide Over effect using <Link to={useBaseUrl("docs/api/FlickingReactiveState")}>indexProgress</Link>.
 
 <Columns>
   <ColumnItem is={12} className="is-flex is-flex-direction-column is-align-items-center">
@@ -1482,7 +1482,7 @@ const getSlideOverStyle = (index) => {
 </Tabs>
 
 ### Cover flow
-> You can create a Cover flow UI using `indexProgress`.
+> You can create a Cover flow UI using <Link to={useBaseUrl("docs/api/FlickingReactiveState")}>indexProgress</Link>.
 
 <Columns>
   <ColumnItem is={12} className="is-flex is-flex-direction-column is-align-items-center">