[MiniRML]

What

The overlap scanner fails with JSONDecodeError: Extra data when GitHub CLI returns more than one page of PRs. gh api --paginate emits separate JSON documents for each page, but open_prs parses its entire output as one document. Request --slurp and flatten the resulting page arrays. The previous test double returned one flat array and concealed the failure; update it to the real response shape.

The response contract is documented in the GitHub CLI API manual.

Tested

Windows 11, Python 3.13. A fixture matching the documented CLI contract supplies 201 PRs over three pages: it fails on the base with Extra data and passes with the fix, retaining the final PR's head and dependency. No live gh invocation or game files needed.

• All 33 overlap-tool tests passed, including empty/single-page results, encoded base names, dependency parsing, export filtering and encoding regressions.
• Conventions and whitespace checks passed.
• Refreshed the changed-file and patch inventory for all 417 open PRs; no other implementation found.
• Merge checks were clean against fix(tools): batch pr_overlap fetch refspecs #4473, fix(tools): follow Depends on chains in pr_overlap #4330, ci: log workflow results and write GitHub job summaries #988 and fix(ci): skip absent overlap reports #4534. fix(tools): link top-of-file insertions to line 1 in pr_overlap #3914 and fix(tools): drop the branch's own pull request in pr_overlap --branch #3911 already conflict with current main in CMakeLists.txt; this PR leaves those pre-existing conflicts unchanged and adds no conflict in its changed files.

Checklist

• Based on current main; no other open PR implements the same fix
• One topic per PR; follow-ups go in a new PR
• No comments in code except technical debt
• Unimplemented paths throw; no runtime stubs changed
• No notes, investigation files or images added to the repository
• New third-party code is a submodule built from source; none added
• Generic behaviour, not specific to one title
• Depends on: none
• Unblocks: none
• AI-assisted: yes

[oneandonlydean]

Closing: gh api --paginate already joins the pages of an array endpoint into one array (main's call returns all 423 open pull requests as one JSON document on gh 2.101), and #4289 removed --slurp because gh before 2.48 rejects it. Reopen with the gh version and the output if a real run gives Extra data.