Summary

Completes the pull request search side of #1934 by adding a minimal_output option to search_pull_requests, so review-queue searches can return compact PR metadata instead of the full GitHub search payload.

Why

list_pull_requests now already maps results into MinimalPullRequest, but search_pull_requests still calls the shared search helper and marshals the full github.IssuesSearchResult. That leaves author-filtered and query-based PR workflows with the verbose user, URL, reaction, and metadata objects called out in the issue.

Fixes #1934

What changed

• pkg/github/pullrequests.go: add the minimal_output parameter to search_pull_requests, default it to the compact path, and keep the raw response available when callers pass minimal_output: false.
• pkg/github/minimal_types.go: map PR search items into a compact result containing total count, incomplete-results state, and essential PR fields from the existing search response.
• pkg/github/pullrequests_test.go: cover the default compact output and the raw-output escape hatch.
• pkg/github/__toolsnaps__/search_pull_requests.snap and README.md: regenerate schema and docs.

MCP impact

• No tool or API changes
• Tool schema or behavior changed
  search_pull_requests gets a new optional minimal_output boolean; default behavior becomes compact, and minimal_output: false preserves the previous raw shape.
• New tool added

Prompts tested (tool changes only)

• "Search open pull requests in github/github-mcp-server that need review, return the essentials only."
• "Search pull requests by author in github/github-mcp-server and return the full raw GitHub search payload."

Security / limits

• No security or limits impact
• Auth / permissions considered
  Both the compact and raw paths use the existing repo scope; this PR does not add any new OAuth scope or permission check.
• Data exposure, filtering, or token/size limits considered
  The compact path reduces returned metadata and does not add extra API calls or new scopes.

Tool renaming

• I am renaming tools as part of this PR (e.g. a part of a consolidation effort)
  • I have added the new tool aliases in deprecated_tool_aliases.go
• I am not renaming tools as part of this PR

Lint & tests

• Linted locally with ./script/lint
./script/lint was not run locally. Direct lint command passed locally: golangci-lint run reported 0 issues.

• Tested locally with ./script/test
./script/test was not run locally. The full race suite was not run locally. Focused package and generation checks passed locally:

• go test ./pkg/github -run "Test_SearchPullRequests|TestSearchPullRequests": passed. Covers the default compact search_pull_requests response and the minimal_output: false raw-compatibility path.

• UPDATE_TOOLSNAPS=true go test ./pkg/github: passed, ok github.com/github/github-mcp-server/pkg/github 5.017s. Regenerated and verified pkg/github/__toolsnaps__/search_pull_requests.snap.

• bash script/generate-docs: passed. Regenerated generated docs from the tool schema.

Docs

• Updated (README / docs / examples)
  Regenerated README/docs and updated pkg/github/__toolsnaps__/search_pull_requests.snap from the tool schema.
• Not needed