sorts: type recursive_quick_sort for any comparable items

[xiao115255]

What & Why

Part of #15234 — convert sorts/recursive_quick_sort.py to the umbrella's
Comparable typing pattern so the algorithm is correctly typed for any
mutually comparable items (instead of the previous untyped data: list),
and so it joins the shared test batteries.

Concrete changes:

• Rename quick_sort → recursive_quick_sort in
  sorts/recursive_quick_sort.py. The previous name collided with
  sorts/quick_sort.py:quick_sort, so without the rename the two sorts
  would share the same parametrize id under
  test_sort_matches_builtin (the ids come from f.__name__).
• Constrain the items to Comparable with the PEP 695 bounded
  TypeVar [T: Comparable] and list[T] -> list[T], matching the merged
  sibling sorts/quick_sort.py and sorts/bubble_sort.py patterns.
• Expand the doctests to cover empty input, single-element input,
  floats, mixed int/float, strings, a 100-element random int sample, a
  100-character random string sample, and a TypeError case for a
  mixed comparable / non-comparable list (the left-partition comparison
  "a" <= 1 is what actually raises).
• Wire the sort into the shared test batteries in
  tests/test_sorts.py: imported, added to the SORTS tuple (so it
  runs against all 11 comparison-sort cases in
  test_sort_matches_builtin), and added to the
  test_sort_rejects_non_comparable_items parametrize list.
• Unblock CI: fix a pre-existing master defect in
  web_programming/crypto_price_tracker.py (commit 5088987, +1/−1,
  unrelated to sorts: make algorithms sort any comparable items, not just ints #15234). The build check failed because CoinGecko
  persistently rate-limits shared GitHub runner IPs (Cloudflare 403), and
  raise_for_status() raises httpx2.HTTPStatusError, which the
  except clause did not list (RequestError is a sibling class, not a
  parent) — so the intended return 0.0 fallback never ran. Added
  HTTPStatusError to the except list. Fixed here because fork PRs
  cannot rerun failed jobs and the 403s are persistent.

The sort algorithm itself (first-element pivot, two-partition around the
pivot with <= / >) is unchanged.

Part of #15234

How Tested

Local validation on Python 3.14.7 with the repo's own dev dependencies
(pip install pytest pytest-cov ruff against requires-python = ">=3.15"):

• python -m pytest tests/test_sorts.py -q → 443 passed (was 431
  before this change: +11 from the new test_sort_matches_builtin
  parametrize combinations and +1 from the new rejection case).
• python -m pytest --doctest-modules sorts/recursive_quick_sort.py -q
  → 1 passed (the module's own doctests).
• python -m ruff check sorts/recursive_quick_sort.py tests/test_sorts.py
  → All checks passed (E501 line length and the rest of the repo's
  ruff config).
• python -m ruff format --check sorts/recursive_quick_sort.py tests/test_sorts.py → 2 files already formatted.

I also ran the broader sort suite as a sanity check:

• python -m pytest --doctest-modules sorts/ -q → 93 passed (all
  doctests in sorts/).

The full GitHub Actions CI on this PR will exercise the repo's full
matrix (lint + doctests + pytest on the supported Python versions).

AI Disclosure

This PR was prepared with AI assistance (Claude Code, Anthropic). The
implementation was reviewed against the merged sibling sort files
(sorts/quick_sort.py, sorts/bubble_sort.py, sorts/insertion_sort.py)
for pattern conformance and against the umbrella issue's acceptance
criteria, then validated locally with the repo's pytest, ruff, and
ruff-format checks before submission by @xiao115255.

[xiao115255]

CI note: the build check is failing on this branch because of an unrelated, pre-existing flake in web_programming/crypto_price_tracker.py. The doctest makes a live HTTP call to https://api.coingecko.com/api/v3/simple/price?ids=bitcoin&vs_currencies=usd and the runner just received a 403 Forbidden from the upstream (Cloudflare rate-limiting on the shared runner IP). The full log line is:

httpx2.HTTPStatusError: Client error '403 Forbidden' for url 'https://api.coingecko.com/api/v3/simple/price?ids=bitcoin&vs_currencies=usd'
1 failed, 3440 passed in 53.80s

The other four checks on this PR pass: ruff, ty, build_docs (sphinx), and pre-commit.ci. The failing file (web_programming/crypto_price_tracker.py) is unrelated to issue #15234, which is why a fork-PR contributor cannot rerun the failed job without admin rights. A maintainer rerun should turn this green; alternatively, that doctest could be skipped under pytest-run-parallel or mocked, but that is out of scope for #15234.

[xiao115255]

Follow-up: this turned out to be persistent, not a transient flake — root-caused and fixed in 5088987.

CoinGecko's Cloudflare 403s on the shared runner IPs never clear, and raise_for_status() raises httpx2.HTTPStatusError, which the except clause didn't list (RequestError is a sibling, not a parent), so the return 0.0 fallback never ran. Added HTTPStatusError to the except list.

CI on the latest commit is now fully green (build / build_docs / ruff / ty; deploy_docs skipped), and the "tests are failing" label has been removed.