[Docs Preview] Bazel Docs: Fix syntax errors in 8.2.1 docs.

[copybara-service]

Bazel Docs: Fix syntax errors in 8.2.1 docs.

Mostly authored by Gemini CLI:

Prompt

You're an experienced tech writer.
Your task is to fix all remaining syntax errors in .mdx files in the current directory.
You can find syntax errors by running "mint validate".

Rules:

• Only fix files mentioned in the output of "mint validate"
• Do not insert blank lines
• Do not change the indentation of lines
• Do not introduce trailing whitespaces
• Do not delete any of the text
• Replace <pre> blocks with Markdown fenced code blocks (three backticks).
• Contents of Markdown fenced code blocks cannot be on the same line as the three backticks.
• Do not merge three or more lines into a single line.
• Do not replace HTML tables with Markdown tables.