ci(timing): budget the job reads and publish a cut-short report (#1930)

[JarryShaw]

• Searched for similar pull requests

• Followed the coding style (make pylint, make mypy, make isort)

• make test passes, and a test case covers the change

• Added a changelog entry — N/A — centralised in docs(changelog): shared 1.5.0 changelog — long-lived, merges last (#610, #616, #617, #618, #620) #657

• ci — workflows or build tooling

A full local --days 7 run of util/ci_timing.py took 16.6 min over 677 API calls, with no retries or rate limiting. That is longer than the job's 15-minute cap. Of that time, 908 s went on job reads, and Unit Tests' 301 reads alone took 734 s, at 2.4 s each, one at a time.

• Job reads now run last, in an order that covers every sample even if reading stops part-way. They stop at --budget-minutes 30.
• If reading stops early, the report is still written, with a note and a warning annotation.
• Progress goes to stderr.
• The step cap is 35 and the job cap is 40, both above the measured run.
• The summary and upload steps run on always().

Tests cover the read order, both budgets still writing a report, the progress output and the nested caps. They fail on main.

Closes #1930

[JarryShaw]

GOOD TO GO at 7085b5e46. A Sonnet cross-review checked the profile logs against the stated phases: 677 calls, 993 s, 601 job reads taking 907.5 s, and no retries or sleeps. Runs whose jobs were never read leave the sample instead of counting as empty, and the budget clock starts when collect starts. The caps nest at 40/35/30, and the YAML parses with concurrency and permissions unchanged. Restoring main's script and workflow makes 8 tests fail. With the fix, test_ci_timing.py and the tier guard pass: 181 tests. The dated measurement in workflows.rst replaces the dated figure that was already there.

[github-actions]

Coverage: 90.07% (unit tier, Python 3.15, 7085b5e46, Unit Tests run success)

Package	Statements	Missed	Branches	Partial	Cover
pcapkit (top level)	104	2	20	2	96.77%
pcapkit/const	19595	881	2618	867	92.11%
pcapkit/corekit	2504	70	792	36	96.54%
pcapkit/dumpkit	276	3	100	3	98.40%
pcapkit/foundation	2916	164	1016	34	93.59%
pcapkit/interface	138	7	52	5	93.68%
pcapkit/protocols	17411	224	4580	189	98.10%
pcapkit/toolkit	872	177	298	8	77.18%
pcapkit/utilities	522	2	158	4	99.12%
pcapkit/vendor	4431	2341	1018	156	43.64%

Per-file detail: the coverage-html artifact of this run.