docs: Update various Expressive Code docs links (#1119)

docs/src/content/docs/guides/authoring-content.md

@@ -239,7 +239,7 @@ Some of the most common examples are shown below:
   ```
   ````
 
-- [Mark selections of text using the `" "` marker or regular expressions](https://github.com/expressive-code/expressive-code/blob/main/packages/%40expressive-code/plugin-text-markers/README.md#marking-entire-lines--line-ranges):
+- [Mark selections of text using the `" "` marker or regular expressions](https://github.com/expressive-code/expressive-code/blob/main/packages/%40expressive-code/plugin-text-markers/README.md#marking-individual-text-inside-lines):
 
   ```js "Individual terms" /Even.*supported/
   // Individual terms can be highlighted, too
@@ -307,7 +307,7 @@ Other languages display inside a code editor-style frame if they include a title
 
 A code block’s optional title can be set either with a `title="..."` attribute following the code block's opening backticks and language identifier, or with a file name comment in the first lines of the code.
 
-- [Add a file name tab with a comment](https://github.com/expressive-code/expressive-code/blob/main/packages/%40expressive-code/plugin-frames/README.md#code-editor-window-frames)
+- [Add a file name tab with a comment](https://github.com/expressive-code/expressive-code/blob/main/packages/%40expressive-code/plugin-frames/README.md#adding-titles-open-file-tab-or-terminal-window-title)
 
   ```js
   // my-test-file.js
@@ -321,7 +321,7 @@ A code block’s optional title can be set either with a `title="..."` attribute
   ```
   ````
 
-- [Add a title to a Terminal window](https://github.com/expressive-code/expressive-code/blob/main/packages/%40expressive-code/plugin-frames/README.md#terminal-window-frames)
+- [Add a title to a Terminal window](https://github.com/expressive-code/expressive-code/blob/main/packages/%40expressive-code/plugin-frames/README.md#adding-titles-open-file-tab-or-terminal-window-title)
 
   ```bash title="Installing dependencies…"
   npm install