Integrated Dynamic Link and its handling for product share

[nb9960]

Fixes #50 and #51

[himanshusharma89]

@nb9960 For multiple issues you should create different PR for the respective issue(if assigned) so that you can gain the appropriate contribution points. Also, you are quite fast, because we'll create a lot of changes here, one of them will Null Safety and Product Object passing. So, you can assign yourself to the issues which will lead us to this PR.

[nb9960]

@himanshusharma89 As I'd already mentioned I chose to resolve #51 for testing of handling dynamic link. Also, these issues don't completely depend on Null safety and product model issues. After defining the product model, just a line of change in navigation will have to be done. (#56 depended on this issue) Though if you wish I can set it as a draft PR.

[himanshusharma89]

Yeah, I got it this PR doesn't depend on these changes but honestly speaking there is a chance of changing the screens in future and also to add a referral system like product sharing, we are far away from that. But no issues you can set it as a draft PR.

We need to add a lot of things before we finalise this, but thank you for such exceptional work right at the beginning.