Improve syntax highlights (#18728)

Closes #18722

- Replace the `@escape` capture name with `@string.escape` for escape
sequences in Go, Python, Regex, Racket, Ruby, and Scheme.
- Rust
  - Add syntax highlighting for escape sequences. Close #18722
- Fix the issue where `@punctuation.delimiter` is being overwritten by
`@operator`.
  - Add the period (".") to `@punctuation.delimiter`.

Release Notes:

- N/A

crates/languages/src/python/highlights.scm

@@ -54,7 +54,7 @@
 
 (comment) @comment
 (string) @string
-(escape_sequence) @escape
+(escape_sequence) @string.escape
 
 [
   "("