Merge rust-bitcoin#4897: docs: Add rustdocs link policy section

168cf28 docs: Add rustdocs link policy section (Tobin C. Harding)

Pull request description:

  With comment
  
  rust-bitcoin#4859 (comment)
  
  we decided to favour links at the bottom of a docs section instead of inline.
  
  Document this policy.


ACKs for top commit:
  apoelstra:
    ACK 168cf28; successfully ran local tests; though FWIW "favour" is British English, not American English


Tree-SHA512: fed46e45ef8f617e71a563f374472f24bee7d424319e26770139606b47eb6aed8a46b6e765de46ac94ed9773ad5c20b1c71336a105e536b04c43169608150828

Author: apoelstra

docs/policy.md

@@ -295,6 +295,18 @@ panics that could theoretically occur because of bugs in our code must not be do
 Example code within the rustdocs should compile and lint with `just lint` without any errors or
 warnings.
 
+### Links
+
+We favour links at the bottom of the docs section:
+
+```rust
+    /// it is a real Taproot script spend (and not some other kind of output contrived
+    /// to have a Taproot-shaped witness). See [BIP-0341] in particular footnote 7, for
+    /// more information.
+    ///
+    /// [BIP-0341]: <https://github.com/bitcoin/bips/blob/master/bip-0341.mediawiki>
+```
+
 ## Derives
 
 We try to use standard set of derives if it makes sense: