Rename Coq requirement prefix to Stdlib

[proux01]

In anticipation of renaming to Rocq.
For backward compatibility, "Coq" still works by being replaced on the fly with "Stdlib" and emiting a warning.

• Added / updated test-suite.

• Added changelog.
• Added / updated documentation.
  • Documented any new / changed user messages.
  • Updated documented syntax by running make doc_gram_rsts.

Overlays (to be merged before the current PR)

• Adapt to https://github.com/coq/coq/pull/19310 coq-community/aac-tactics#148
• Adapt to https://github.com/coq/coq/pull/19310 LPCIC/coq-elpi#662
• Account for Coq => Stdlib replacement JasonGross/coq-tools#209
• Adapt to https://github.com/coq/coq/pull/19310 mit-plv/coqutil#119

Overlays (to be merged in sync with the current PR)

• Adapt to https://github.com/coq/coq/pull/19310 coq-community/coq-dpdgraph#133
• Adapt to https://github.com/coq/coq/pull/19310 ejgallego/coq-lsp#809
• Adapt to https://github.com/coq/coq/pull/19310 MetaCoq/metacoq#1093
• Adapt to https://github.com/coq/coq/pull/19310 QuickChick/QuickChick#384
• Adapt to https://github.com/coq/coq/pull/19310 ejgallego/coq-serapi#422

[Villetaneuse]

Is this a record for the number of reviewers? 😄

[coqbot-app]

🔴 CI failures at commit 72e23e7 without any failure in the test-suite

✔️ Corresponding jobs for the base commit 439641c succeeded

❔ Ask me to try to extract minimal test cases that can be added to the test-suite

🏃 @coqbot ci minimize will minimize the following targets: ci-elpi_hb, ci-fiat_crypto_legacy, ci-metacoq

• You can also pass me a specific list of targets to minimize as arguments.
• If you tag me saying @coqbot ci minimize all, I will additionally minimize the following target (which I do not suggest minimizing): ci-coq_tools (because coq-tools is too sensitive to the output of coqc to be minimized at this time (instead, @JasonGross can help diagnose and fix the issue))

[silene]

Unless someone proposes a solution for the following kind of issue, I will merge by the end of the week.

Module Coq. Definition foo := ... End Coq.
Check Coq.foo. (* not found *)

[mattam82]

Shouldn't we change so that it at least warns of the Coq -> Stdlib renaming in addition to the Not_found in that case? And mention in the changelog this incompatibility

[proux01]

Done

[proux01]

@silene CI green (fcsl failure is unrelated)

[silene]

@coqbot merge now

[coqbot-app]

@silene: Please take care of the following overlays:

• 19310-proux01-stdlib-logical-name.sh