feat: make sdk.Context implement context.Context

[aaronc]

Description

This:

• addresses an issue with the way WrapSDKContext was done in that it doesn't use the context.Context that is already inside sdk.Context
• it allows sdk.Context to be used as a context.Context directly
• it also walks back the deprecation of Value and WithValue from Simplify context #4706 as I actually think these are useful, and trying to put everything directly into Context as a bag of variables rather than attaching it using something like WithValue makes the SDK less extensible

---

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[ValarDragon]

LGTM seems good to merge.

Should there be comments on the Deadline, Done, Err functions explaining that they are there for interface matching, and just pass through to the underlying ctx key value store?

Also as an aside can c.ctx be renamed to c.additional_data or something? I was pretty confused by the c.ctx on first pass 😅

(Neither of those comments really matter imo, and don't block merge)

[robert-zaremba]

utACK

[robert-zaremba]

can c.ctx be renamed to c.additional_data or something?

c.ctx was already there. it's the "go stdlib" context. It's private member, so IMHO, not a big deal, but I'm not against renaming eg to stdctx if this makes confusions.

[blushi]

can c.ctx be renamed to c.additional_data or something?

c.ctx was already there. it's the "go stdlib" context. It's private member, so IMHO, not a big deal, but I'm not against renaming eg to stdctx if this makes confusions.

@aaronc ping

[aaronc]

can c.ctx be renamed to c.additional_data or something?

c.ctx was already there. it's the "go stdlib" context. It's private member, so IMHO, not a big deal, but I'm not against renaming eg to stdctx if this makes confusions.

@aaronc ping

I renamed it to baseCtx which I think is the role it plays