* Shard plugin evaluation via executionShard tag in eval.yaml
MCP-heavy plugins like dotnet-msbuild reliably exhaust the GitHub-hosted runner host after ~87 min of cumulative MCP traffic (Copilot CLI plus dotnet dnx Microsoft.AITools.BinlogMcp child processes), which has produced no dashboard data for dotnet-msbuild scheduled runs since 2026-05-20. Cutting per-runner concurrency alone was insufficient: at the default 18-way concurrency the runner OOMs in 17-30 min; at 3-way it survives longer but still hits a host-level termination at ~87 min.
Two mitigations, both required:
1. Sharding (this change). The discover step reads an optional top-level 'executionShard:' string from each tests/<plugin>/<skill>/eval.yaml and groups skills by tag, emitting one matrix entry per shard so each shard runs on a fresh runner. Untagged skills fall into a 'default' bucket. Plugins where all skills resolve to a single bucket emit one entry (unchanged behavior). The validator already calls IgnoreUnmatchedProperties so no Models.cs change is needed. Shard names follow '<plugin>--shard-<tag>' so the existing 'skill-validator-results-<plugin>--*' artifact glob keeps working.
2. Per-MCP-plugin concurrency caps (already in place). When plugin.json declares mcpServers, parallelism is forced to 1x3x1 with --judge-timeout 600 to avoid acute OOM within a shard.
Also adds a workflow_dispatch 'plugin' input for targeted re-runs of a single plugin, and tags 10 dotnet-msbuild eval.yamls (heavy/medium); the remaining 8 fall into 'default'. Empirically the three shards complete in parallel in ~30-40 min each, well inside the 180-min job timeout, and successfully upload dashboard data.
* Address PR review: lenient shard regex and validate dispatch plugin input
- executionShard regex now tolerates optional leading whitespace, so an accidentally indented key still groups correctly instead of silently falling back to the default bucket.
- workflow_dispatch 'plugin' input is now validated against ^[a-zA-Z0-9._-]+$ before any Join-Path/Test-Path use, preventing path-traversal style values (e.g. '../foo') from being injected into filesystem paths.
* dotnet-msbuild: register AITools.BinlogMcp and use it from binlog-failure-analysis
Adds the AITools.BinlogMcp MCP server (pulled via dnx from the dotnet-eng public NuGet feed, prerelease, no version pin) to the dotnet-msbuild plugin and rewrites the binlog-failure-analysis SKILL.md to lead with the MCP tools (binlog_overview, binlog_errors, binlog_search, binlog_items, binlog_properties, binlog_imports, binlog_nuget). The text-log replay workflow is kept as a fallback for environments without the MCP.
* Improve skills
* Reflect PR comments
Aditya Mandaleeka