style: prefer non-fancy quotation marks

[michen00]

Problem

The repository currently mixes two distinct apostrophe characters: the typographic right single quotation mark (U+2019 or ’) and the ASCII apostrophe (U+0027 or '). This inconsistency provides no functional benefit and conflicts with the project's own guidance in CONTRIBUTING.md:

Do not use fancy quotes, dashes, and such; the Markdown processor will handle that.

Using typographic punctuation in source-controlled text introduces unnecessary variability without conveying additional meaning.

Solution

This change normalizes the following:

• apostrophes to the ASCII character U+0027 '
• double quotes to the ASCII character U+0022 "

2e12e81 replaces fancy quotes in Markdown files throughout the repository; past covenant versions and LICENSE.md were not modified.

Rationale / Benefits

• Consistency with project standards: Aligns the text with explicit contributor guidance, reducing ambiguity about acceptable punctuation.
• Improved diff clarity: Curly quotes are visually subtle but byte-distinct, which can produce noisy or misleading diffs for otherwise trivial edits.
• Copy/paste and tooling robustness: U+0027 ' is reliably handled across editors, terminals, linters, static analyzers, and search tools. Typographic quotes are a common source of accidental encoding and matching issues.
• Lower contributor friction: Contributors using plain-text editors or environments that lack support for “smart quotes” will not accidentally introduce stylistic inconsistencies.
• Principle of least surprise: ASCII punctuation behaves exactly as expected in Markdown, source control, and downstream tooling, with no hidden semantics.

The change is intentionally minimal, but it removes an unnecessary source of inconsistency and aligns the text with both project policy and common software development practice.

Remaining instances of fancy quotes

• LICENSE.md: ’ (U+2019), “ (U+201C), and ” (U+201D)
• code-of-conduct.zh-cn.md 1.4: “ (U+201C) and ” (U+201D)
• code-of-conduct.zh-cn.md 2.0: “ (U+201C) and ” (U+201D)

Other changes

• Normalized whitespace in .md files
• Formatted an email address
• Added .git-blame-ignore-revs

Related

• style: prefer U+0027 (') over U+2019 (’) #1575 (recreated with new branch name)
• style: prefer U+0027 (') over U+2019 (’) #1580 (condensed fancy quote commits; additional formatting commits)