List every contract in each API doc section (#4848)

Co-authored-by: Hadrien Croubois <hadrien.croubois@gmail.com>

contracts/access/README.adoc

@@ -5,7 +5,9 @@ NOTE: This document is better viewed at https://docs.openzeppelin.com/contracts/
 
 This directory provides ways to restrict who can access the functions of a contract or when they can do it.
 
-- {AccessControl} provides a general role based access control mechanism. Multiple hierarchical roles can be created and assigned each to multiple accounts.
+- {AccessManager} is a full-fledged access control solution for smart contract systems. Allows creating and assigning multiple hierarchical roles with execution delays for each account across various contracts.
+- {AccessManaged} delegates its access control to an authority that dictates the permissions of the managed contract. It's compatible with an AccessManager as an authority.
+- {AccessControl} provides a per-contract role based access control mechanism. Multiple hierarchical roles can be created and assigned each to multiple accounts within the same instance.
 - {Ownable} is a simpler mechanism with a single owner "role" that can be assigned to a single account. This simpler mechanism can be useful for quick tests but projects with production concerns are likely to outgrow it.
 
 == Core

contracts/governance/README.adoc

@@ -30,6 +30,8 @@ Counting modules determine valid voting options.
 
 Timelock extensions add a delay for governance decisions to be executed. The workflow is extended to require a `queue` step before execution. With these modules, proposals are executed by the external timelock contract, thus it is the timelock that has to hold the assets that are being governed.
 
+* {GovernorTimelockAccess}: Connects with an instance of an {AccessManager}. This allows restrictions (and delays) enforced by the manager to be considered by the Governor and integrated into the AccessManager's "schedule + execute" workflow.
+
 * {GovernorTimelockControl}: Connects with an instance of {TimelockController}. Allows multiple proposers and executors, in addition to the Governor itself.
 
 * {GovernorTimelockCompound}: Connects with an instance of Compound's https://github.com/compound-finance/compound-protocol/blob/master/contracts/Timelock.sol[`Timelock`] contract.
@@ -66,6 +68,8 @@ NOTE: Functions of the `Governor` contract do not include access control. If you
 
 === Extensions
 
+{{GovernorTimelockAccess}}
+
 {{GovernorTimelockControl}}
 
 {{GovernorTimelockCompound}}

contracts/metatx/README.adoc

@@ -3,6 +3,11 @@
 [.readme-notice]
 NOTE: This document is better viewed at https://docs.openzeppelin.com/contracts/api/metatx
 
+This directory includes contracts for adding meta-transaction capabilities (i.e. abstracting the execution context from the transaction origin) following the https://eips.ethereum.org/EIPS/eip-2771[ERC-2771 specification].
+
+- {ERC2771Context}: Provides a mechanism to override the sender and calldata of the execution context (`msg.sender` and `msg.data`) with a custom value specified by a trusted forwarder.
+- {ERC2771Forwarder}: A production-ready forwarder that relays operation requests signed off-chain by an EOA.
+
 == Core
 
 {{ERC2771Context}}

contracts/utils/README.adoc

@@ -5,14 +5,30 @@ NOTE: This document is better viewed at https://docs.openzeppelin.com/contracts/
 
 Miscellaneous contracts and libraries containing utility functions you can use to improve security, work with new data types, or safely use low-level primitives.
 
+ * {Math}, {SignedMath}: Implementation of various arithmetic functions.
+ * {SafeCast}: Checked downcasting functions to avoid silent truncation.
+ * {ECDSA}, {MessageHashUtils}: Libraries for interacting with ECDSA signatures.
+ * {SignatureChecker}: A library helper to support regular ECDSA from EOAs as well as ERC-1271 signatures for smart contracts.
+ * {MerkleProof}: Functions for verifying https://en.wikipedia.org/wiki/Merkle_tree[Merkle Tree] proofs.
+ * {EIP712}: Contract with functions to allow processing signed typed structure data according to https://eips.ethereum.org/EIPS/eip-712[EIP-712].
  * {ReentrancyGuard}: A modifier that can prevent reentrancy during certain functions.
  * {Pausable}: A common emergency response mechanism that can pause functionality while a remediation is pending.
- * {SafeCast}: Checked downcasting functions to avoid silent truncation.
- * {Math}, {SignedMath}: Implementation of various arithmetic functions.
- * {Multicall}: Simple way to batch together multiple calls in a single external call.
- * {Create2}: Wrapper around the https://blog.openzeppelin.com/getting-the-most-out-of-create2/[`CREATE2` EVM opcode] for safe use without having to deal with low-level assembly.
+ * {Nonces}: Utility for tracking and verifying address nonces that only increment.
+ * {ERC165, ERC165Checker}: Utilities for inspecting interfaces supported by contracts.
+ * {BitMaps}: A simple library to manage boolean value mapped to a numerical index in an efficient way.
  * {EnumerableMap}: A type like Solidity's https://solidity.readthedocs.io/en/latest/types.html#mapping-types[`mapping`], but with key-value _enumeration_: this will let you know how many entries a mapping has, and iterate over them (which is not possible with `mapping`).
  * {EnumerableSet}: Like {EnumerableMap}, but for https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets]. Can be used to store privileged accounts, issued IDs, etc.
+ * {DoubleEndedQueue}: An implementation of a https://en.wikipedia.org/wiki/Double-ended_queue[double ended queue] whose values can be removed added or remove from both sides. Useful for FIFO and LIFO structures.
+ * {Checkpoints}: A data structure to store values mapped to an strictly increasing key. Can be used for storing and accessing values over time.
+ * {Create2}: Wrapper around the https://blog.openzeppelin.com/getting-the-most-out-of-create2/[`CREATE2` EVM opcode] for safe use without having to deal with low-level assembly.
+ * {Address}: Collection of functions for overloading Solidity's https://docs.soliditylang.org/en/latest/types.html#address[`address`] type.
+ * {Arrays}: Collection of functions that operate on https://docs.soliditylang.org/en/latest/types.html#arrays[`arrays`].
+ * {Base64}: On-chain base64 and base64URL encoding according to https://datatracker.ietf.org/doc/html/rfc4648[RFC-4648].
+ * {Strings}: Common operations for strings formatting.
+ * {ShortString}: Library to encode (and decode) short strings into (or from) a single bytes32 slot for optimizing costs. Short strings are limited to 31 characters.
+ * {StorageSlot}: Methods for accessing specific storage slots formatted as common primitive types.
+ * {Multicall}: Abstract contract with an utility to allow batching together multiple calls in a single transaction. Useful for allowing EOAs to perform multiple operations at once.
+ * {Context}: An utility for abstracting the sender and calldata in the current execution context.
 
 [NOTE]
 ====
@@ -45,6 +61,8 @@ Because Solidity does not support generic types, {EnumerableMap} and {Enumerable
 
 {{Pausable}}
 
+{{Nonces}}
+
 == Introspection
 
 This set of interfaces and contracts deal with https://en.wikipedia.org/wiki/Type_introspection[type introspection] of contracts, that is, examining which functions can be called on them. This is usually referred to as a contract's _interface_.
@@ -86,3 +104,5 @@ Ethereum contracts have no native concept of an interface, so applications must
 {{StorageSlot}}
 
 {{Multicall}}
+
+{{Context}}