docs: add ## Notes section to time/quarter-of-year README

[Planeshifter]

Description

This pull request adds the ## Notes section present in 17 of 19 sibling @stdlib/time/* packages (~89% conformance) to the quarter-of-year README. The boilerplate text matches the disclaimer added to iso-weeks-in-year (#12313), day-of-quarter, and day-of-year (#12369). quarterOfYear() accepts a Date argument and uses Date.prototype.getMonth() (local time), so the daylight-savings / timezone disclaimer is semantically applicable, matching sibling day-of-quarter.

Namespace summary

• Members analyzed: 19 (@stdlib/time/* direct children with package.json)
• Structural features with clear majority (≥75%): file_tree (set), pkg_json.top_keys, readme_sections (set and sequence), test_files, examples_files
• Semantic features with clear majority: errorConstruction (uniformly format), @example presence, JSDoc tag families (matched to per-function semantics)
• Features excluded for no clear majority: benchmark/benchmark.js presence (2/19), pkg_json.scripts_keys, pkg_json.stdlib_keys

quarter-of-year

Sole outlier with confirmed, mechanically fixable drift. The README jumped from ## Usage directly to ## Examples, skipping the ## Notes section present in 17 of 19 siblings (89.5% conformance). The Notes content is identical verbatim across all conformant siblings; the disclaimer applies semantically because quarterOfYear reads the month via Date.prototype.getMonth() in local time.

Validation

• Structural extraction: file trees, package.json shapes, README section sets and sequences, test/benchmark/example filenames across all 19 members.
• Semantic extraction: error-construction style, JSDoc tag families, dependencies via require(), public-function shapes — scanned directly across all 19 lib/main.js files.
• Three-agent validation on the surviving outlier (cross-reference and structural review) — both returned confirmed-drift. Semantic-review skipped (purely structural feature).
• Deliberately excluded: base (meta sub-namespace), tic/toc lacking CLI infrastructure (no shell use case; CLI not present in ≥90% of stdlib outside this namespace), and benchmark/benchmark.js adds across 17 packages (below 75% majority threshold).
• Generator-owned files (docs/repl.txt, docs/types/index.d.ts) intentionally not touched, despite some prior maintainer PRs (docs: document Date input and add Notes section in time/iso-weeks-in-year #12313) editing them; this PR plays conservative on generator-owned scope.

Related Issues

No.

Questions

No.

Other

Recent precedent for this exact correction on adjacent siblings: #12313 (iso-weeks-in-year) and #12369 (day-of-quarter, day-of-year). Both added the verbatim Notes block in the same README position.

Checklist

• Read, understood, and followed the contributing guidelines.

AI Assistance

• Yes
• No

If you answered "yes" above, how did you use AI assistance?

• Code generation (e.g., when writing an implementation or fixing a bug)
• Test/benchmark generation
• Documentation (including examples)
• Research and understanding

Disclosure

This PR was authored by Claude Code as part of a cross-package API drift detection routine: structural and semantic features extracted across all 19 direct children of @stdlib/time/, majority pattern identified per feature (75% threshold), single high-signal outlier (quarter-of-year missing ## Notes) confirmed via multi-agent validation, and the verbatim sibling boilerplate applied.

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@stdlib-js/reviewers

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Generated by Claude Code

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
time/quarter-of-year	$\color{green}129/129$ $\color{green}+100.00\%$	$\color{green}17/17$ $\color{green}+100.00\%$	$\color{green}1/1$ $\color{green}+100.00\%$	$\color{green}129/129$ $\color{green}+100.00\%$

The above coverage report was generated for the changes in this PR.