Rollup merge of #148448 - rustbot:docs-update, r=ehuss

Update books

## rust-lang/book

6 commits in af415fc6c8a6823dfb4595074f27d5a3e9e2fe49..f660f341887c8bbcd6c24fbfdf5d2a262f523965
2025-10-28 01:41:51 UTC to 2025-10-24 15:39:51 UTC

- Update to Rust 1.90 (rust-lang/book#4545)
- Update to Rust 1.89 (rust-lang/book#4544)
- Update to Rust 1.88 (rust-lang/book#4543)
- Update to Rust 1.87 (rust-lang/book#4542)
- Update to Rust 1.86 (rust-lang/book#4541)
- Remove unused subheadings (rust-lang/book#4538)

## rust-lang/edition-guide

1 commits in e2ed891f00361efc26616d82590b1c85d7a8920e..5c621253d8f2a5a4adb64a6365905db67dffe3a2
2025-10-23 14:13:01 UTC to 2025-10-23 14:13:01 UTC

- Add back the link for never_type_fallback_flowing_into_unsafe (rust-lang/edition-guide#378)

## rust-lang/reference

12 commits in 752eab01cebdd6a2d90b53087298844c251859a1..e122eefff3fef362eb7e0c08fb7ffbf5f9461905
2025-10-28 20:52:27 UTC to 2025-10-21 19:42:06 UTC

- Remove custom redirect scripts (rust-lang/reference#2065)
- Avoid specifying "last import wins" for MBEs (rust-lang/reference#2057)
- Add caveats about mutable references in consts (rust-lang/reference#2058)
- Move punctuation index to an appendix, and expand for other syntaxes (rust-lang/reference#2061)
- Use American spelling for "labeled" (rust-lang/reference#2066)
- Remove rules from names intro (rust-lang/reference#2060)
- Minor adjustments to inner/outer attribute definitions (rust-lang/reference#2059)
- Change underscore to be a keyword (rust-lang/reference#2049)
- Update `proc_macro_attribute` to use the attribute template (rust-lang/reference#1889)
- Update `proc_macro` to use the attribute template (rust-lang/reference#1887)
- Update `macro_use` to use the attribute template (rust-lang/reference#1886)
- Update `macro_export` to use the attribute template (rust-lang/reference#1885)

## rust-lang/rust-by-example

7 commits in 2c9b490d70e535cf166bf17feba59e594579843f..160e6bbca70b0c01aa4de88d19db7fc5ff8447c3
2025-11-03 12:26:45 UTC to 2025-10-22 13:19:06 UTC

- Fix typos in flow_control/match/binding (rust-lang/rust-by-example#1971)
- add clarification on overflowing_literals lint (rust-lang/rust-by-example#1970)
- Update enum_use.md (rust-lang/rust-by-example#1960)
- Remove weird extra spaces in code (rust-lang/rust-by-example#1962)
- Include a link to The Rust Reference in flow_control/match/destructuring (rust-lang/rust-by-example#1963)
- Add an example showing pattern binding when matching several values in a match arm (rust-lang/rust-by-example#1966)
- Fix typo in linked list length calculation comment (rust-lang/rust-by-example#1968)